Character Profiles - Major OCs

WARNING: MAJOR SPOILERS AHEAD, READ AT YOUR OWN RISK!
Notes:
* This profile will cover all "pure OCs" (i.e. those not meant to match a character shown in canon material).
* For the purposes of definition, a "major" character is one that appears in six or more stories.
* Major canon characters and OC Stand Ins will be found in the Major Canons entry.
* References to canon material (as defined above) will be given in bold. References within the stories themselves will be in italics.

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Captain of the Guard Gibraltar (Headcanon Voice: Harrison Ford) - Unicorn stallion (similar color scheme to Mayor Mare), somewhere in the lower 50s in terms of age. Captain of the Canterlot Guard as of "Nightmare Moon's" return and Shining Armor's immediate predecessor in the position. Special talent is what humans would call "earthbending". Has two colts, both in field service with the Guard themselves. (First mentioned in The Long Road Home, first appearance in A New Mission, Games We Play).
Having arrived in Canterlot in what he had hoped was a kind of professional retirement after many long years in field service, instead Gibraltar found himself caught up in the fulfillment of the thousand year prophecy of "Nightmare Moon's" return and all the fallout that resulted from that. We first see him leading the honor guard ceremony that promoted then-Lieutenant Shining Armor to Lieutenant Captain - one of the more immediate consequences of Princess Luna's arrival in Canterlot. (A New Mission)
After Luna's return, Gibraltar worked closely with Princess Celestia to reorganize the Royal Guard to allow Luna a full service. This included reconstituting the nighttime "Luna Shift" with Shining Armor in command. The reorganization aggravated preexisting tensions within the Guard, compounding Gibraltar's headaches. (The Luna Shift)
After Cadance's arrival in Canterlot, Gibraltar became caught up in the conspiracies of the Agents of Chaos, often acting as mentor and source of information to both the Princesses and Shining Armor. He also often assisted in defeating their schemes. (Cadance onward)
After being assigned "Operation Shield" by Princess Celestia, he summoned Lieutenant Captain Fidelitas to execute the operation, despite Fidelitas' own misgivings and agreement that Shining Armor would be better for the assignment. Quickly, he found himself caught up in Aten's "shenanigans", unable to do much to help Shining Armor and only escaping after the latter's triumph. (Operation Shield)
He discussed with Shining Armor about how much he could do to help Moon Dancer and her mother, and later oversaw the punishment of Ventas after his "defection" following the conspiracy against Star Dancer being executed. (Broken Fences)
After the discovery of an unconscious Lilly Withers dumped on the Canterlot mountainside, Gibraltar took it upon himself to summon her colt under his command in an attempt to obtain information about the fate and whereabouts of her and her husband. This effort was partly successful, allowing Buck Withers to learn that his father had once been an Agent of Chaos. Later, Gibraltar attended the funeral of Lilly Withers and had a conversation with Shining Armor about an "oncoming storm". He also requested Lieutenant Skyver be a pallbearer at that funeral beforehand. (Pocketful of Posies)
When Lieutenant Captain Aten attempted to eject Spike from Canterlot Castle while Spike was on a mission from Twilight Sparkle, Gibraltar cited an old exemption to the city and castle rules that allowed him to overrule Aten's orders and let Spike continue on his mission. When Aten objected, Gibraltar told him the first in what turned out to be a series of stories centered around Twilight's time as Celestia's apprentice. This information includes some information about his previous service - having been in "all points of the compass" and having taken the role of Captain of the Canterlot Guard six years before. (In Praise of Twilight)
Gibraltar once again had to deal with a Celestia-generated assignment in Zecora, initially letting Lieutenant Crispin in Ponyville deal with it and only sending reinforcements when requested by Crispin following Agents of Chaos opposition.
Gibraltar attended the board of inquiry following the parasprite infestation in Ponyville and later, acting on Celestia's orders, bailed out two imprisoned Wonderbolts and escorted them back to the Wonderbolt offices in Canterlot. (The Parasprite Project)
Gibraltar had a briefing with Shining Armor about "Mr. Hoofer" and the EIA after the attack on Hoity Toity's boutique, and ultimately followed Celestia's orders in authorizing a raid on the EIA headquarters. He also conducted an interview with an defector from the Agents of Chaos, which seemed to have lead to the defector's assassination a short while later. (High Fashion High Noon)
Gibraltar again briefed Shining Armor in Circle of the Moon about Celestia's plans to cancel Nightmare Night celebrations, working with Shining to pass along an alternate batpony proposal to replace the canceled Canterlot celebrations.
Gibraltar gave a briefing to the whole night shift about the events of the Best Young Flyers competition seen in Sonic Rainboom, passing along knowledge and warning from Princess Celestia to the whole shift about the Agents of Chaos, as well as personally warning Shining Armor of Captain Spitfire's temper. Later, he was caught up in the main rebel attack of "Operation Whirlwind" and lead the efforts to counterattack - after the rebel attack was defeated, he left Lieutenant Skyver in operational authority of the Canterlot Guard and took Shining Armor and Princess Luna in an attempt to warn Princess Celestia in the castle about the rebel attack. Finally, he assisted in defeating Agent Snake in the castle's throne room. (Rainboom Revolution)
Gibraltar was kept quite busy in the aftermath of the failed Operation Whirlwind - not just in attempting to calm Celestia's apparent paranoia over a specific "Statue of Discord" in the castle gardens, but in patching together a new morning shift after most of the old one turned traitor in Whirlwind, and investigating the depths of Aten's treachery afterward. (Consequences)
Barely after the dust had settled on Aten's rebellion, Captain Gibraltar found history repeating itself with Lieutenant Troilus' conspiracy against pegasi, first manifesting as an attempt to hold the "Cutie Mark Crusaders" hostage that Gibraltar had to help thwart and then later as more direct attacks against pegasi under his command. (The Crusaders, Phoenix Down)
In Mission to Appleloosa, he was the "passthrough" giver of Celestia's assignment to the Ponyville Royal Guard contingent lead by Lieutenant Meadow Song.
He was seen several times In A Just Cause. The first time was after the Grand Galloping Gala had been crashed by the Element Bearers. After summoning Shining Armor and Princess Cadance to Canterlot Castle, he gave the former an assignment to find an unaccounted-for Princess Celestia and Element Bearers. The second time was the morning after the Gala; he was present as part of a meeting regarding the missing Prince Blueblood when Java Jive arrived with a vital piece of information about his whereabouts. After learning additional information about Lieutenant Troilus from Stratocumulus, he was dispatched to investigate thefts related to the illegal Operation Hornpoint. In the process, he found the dead Head Groundskeeper and from this was convinced to initiate Operation Just Cause with Shining Armor as its commander.
Like many of his comrades, he was concerned about Princess Celestia's opening of the castle statue garden to public tours, and initially attempted to counter Discord after he had been released. During this battle, he was incapacitated by breaking his front legs, forcing Lieutenant Captain Shining Armor to become Acting Captain, although Gibraltar was still able to do paperwork and be updated on events while in the medical ward. Gibraltar eventually confirmed that he intended Shining Armor to be his permanent successor once the emergency was over. (The Return of Harmony, The Day of Discord)
Shining Armor helped Gibraltar move out of the Captain's suite, both showing Celestia having confirmed Shining as Gibraltar's successor and giving the captain-to-be chance to meet both of Gibraltar's colts. It was during this move Gibraltar first learned Shining intended to propose to Cadance. (Zero Point)

Lieutenant Captain Fidelitas (Headcanon Voice: Jason David Frank) - Unicorn stallion, somewhere in the low 30s in terms of age. His cutie mark is a pair of crossed swords. At the time of "Nightmare Moon's" return, he was the afternoon shift commanding officer of the Canterlot Royal Guard. Shining Armor was one of his subordinates until being promoted to equal rank. Although not mentioned by name, he was the stallion that informed Lieutenant Shining Armor of Princess Celestia summoning him to her chambers, and then later on summoning him to the throne room in fulldress for the ceremony that would promote Shining Armor to Lieutenant Captain. Fidelitas was also present as part of the promotion ceremony. (It's All Real, A New Mission, Games We Play)
Fidelitas was present during the botched presentation ceremony and assisted Shining Armor in getting Princess Luna to Canterlot Hospital. He then stayed with Shining and Luna at the hospital for some time, telling Shining the story of how eight years before he had saved the lives of many of his fellow guards with his special talent - a grey "magic sword" that extends from his horn. This act, conducted when he was a Guard Upper Class, apparently got him noticed by Celestia, who approved his field promotion to Lieutenant and then a few years afterward transferred him to Canterlot as a Lieutenant Captain. (The Luna Shift)
Shortly before Princess Cadance's arrival in Canterlot, Fidelitas had conversations with Lieutenant Vesper, Princess Celestia and Lieutenant Captain Shining Armor. The conversation with Vesper was about the relatively little-known bat pony customs and traditions, while the conversation with the other two was about Cadance's chariot. (Cadance)
After the defeat of "Operation Love Lost", Fidelitas assisted Princess Celestia in the public execution of the captured Agents of Chaos. We also learn more about his past. He was born and raised in a northern town called Whitehorse (near the future border of the Crystal Empire) and was in training to be a sculptor when that town suffered a windigo attack. His bravery fighting off the windigos alongside the Royal Guards prompted an offer for him to join them, and he quickly rose through the ranks (partly from the incident mentioned in The Luna Shift) to become the afternoon shift commander in Canterlot. Princess Celestia had placed him there to protect and incubate Shining Armor's own rise in the Guard ranks, and after Luna's arrival was now tasked with "having Shining's back" against the internal enemies. (Games We Play onward)
He was assigned by Captain Gibraltar to head "Operation Shield", an effort to prevent repeats of the Ursa Minor attack on Ponyville. Although he pointed out Shining Armor would be better for the assignment, he accepted it anyways and was assigned two work teams to carry it out. Despite repeated problems posed by Agents of Chaos embedded in Ponyville, he nevertheless was able to start the construction necessary to fulfill the assignment and returned to Canterlot afterward, where he was also an eyewitness to Shining Armor's first successful enclosing of Canterlot in a forcefield bubble. While in Ponyville, he had an honest moment with Twilight Sparkle about her brother and Princess Luna. (Operation Shield)
Fidelitas next appears in In Praise of Twilight, where one of the stories recounted is from when he was recently promoted to the Lieutenant Captain rank and informally sparred with the lower-ranked Shining Armor, who then had been assigned to his command.
He was present at the meeting outlining "Operation Integration", but was otherwise not involved in the subsequent events. This meeting served to reinforce the antipathy that existed between him and his morning-shift counterpart. (Zecora)
He helped break the news about the parasprite infestation in Ponyville to Shining Armor. Later we learn that he uses his special talent to carve an ice statue for the annual Royal Guard Hearth's Warming party - the statue of Luna he made after Luna's return was destroyed in Agent Snake's attack on the party. (The Parasprite Project, A Hearth's Warming Caper)
In the aftermath of Operation Whirlwind, he was assigned to be a temporary morning shift commander, executing the wills of Princess Celestia and Captain Gibraltar in giving out some of the consequences of the failure of Whirlwind. (Consequences)
Barely after the dust had settled on Aten's rebellion, Fidelitas found history repeating itself with Lieutenant Troilus' conspiracy against pegasi, first manifesting as an attempt to hold the "Cutie Mark Crusaders" hostage that he had to help thwart. (The Crusaders)
He was present during the meeting that initiated Operation Just Cause. Initially, he volunteered to lead the operation in place of the controversial pick of Shining Armor, but was overruled by Captain Gibraltar. As a consolation, he was allowed to help Shining Armor select the ponies involved in the operation. (A Just Cause)
Like many of his comrades, he was concerned about Princess Celestia's opening of the castle statue garden to public tours, and initially attempted to counter Discord after he had been released. During this fight, Fidelitas overexerted his unicorn magic, forcing him to retreat with a migraine headache upon the arrival of Captain Gibraltar and Lieutenant Captain Shining Armor to the statue garden. This headache did not last long, and Fidelitas was later able to temporarily run the castle guard during Shining Armor (who had become Acting Captain at this point) attempting a second time to fight against Discord's scheme. (The Return of Harmony, The Day of Discord)
On Celestia's orders, he gave a confidential scroll meant to be read by Granny Smith to Lieutenant Crispin when the latter intended to visit Ponyville for a weekend. He was also seen as the unicorn representative acknowledging Shining Armor as Captain of the Guard during the "passing the torch" ceremony. (Zero Point)

Lieutenant Captain Vesper (Headcanon Voice: Peter New) - Bat pony stallion, leader of The Thestrals and last Keeper of the Compact. Formerly leader of a quasi-cult within the Royal Guard that kept knowledge of Princess Luna intact but secret during her exile, he pledged his loyalty and the bat ponies under his command in service to the restored Luna and Lieutenant Captain Shining Armor. After that point, Vesper became one of Shining's most trusted and faithful Lieutenants. (The Luna Shift)
During Princess Cadance's arrival in Canterlot, he had a conversation with Lieutenant Captain Fidelitas regarding bat pony customs and traditions, then after Fidelitas had been relieved by Shining Armor Vesper took charge of the Royal Guard squad responsible for taking charge of the chariot and stowing it away after Cadance's arrival. He also served as the lead member of the "representative guard" introducing Cadance to Luna. After the disastrous introduction, he led the escort of Cadance to her suite. Finally, along with Lieutenant Stratocumulus, he investigated the Weather Ministry in response to the Agents of Chaos executing "Operation Love Lost". After the defeat of "Operation Love Lost", Lieutenant Vesper was given commendations. (Cadance, Games We Play)
Lieutenant Vesper and his bat pony command played a significant role in thwarting an attempt to abduct Princess Luna by the Griffon Ambassador. Later, the griffon defector was assigned provisionally under his direct command, and by the time of "Operation Shield" Vesper declared to Shining Armor that the griffon defector was ready to assume full duties after extensive training. (Excelsior, Operation Shield)
Vesper and his squad were tasked with finding Moon Dancer, who was intending to runaway from Canterlot, while the conspiracy against Star Dancer was being executed. He and his squad succeeded in finding Moon Dancer and preventing her from running away from Canterlot, but could not do anything else to help Star Dancer. (Broken Fences)
Shining Armor mentions to Buck Withers that Vesper and his bat ponies were looking for his duty partner, which had went AWOL and allowed for the assassination attempt on Buck. (Pocketful of Posies)
Vesper and his command were heavily involved in Circle of the Moon, publicly opening their previous secret rites with Celestia's approval to replace cancelled Nightmare Night celebrations. This was done in the form of a play called "Circle of the Moon", performed by Vesper and his command with some help from Princesses Celestia and Cadance as well as the Element Bearers in Ponyville.
Vesper was one of the Lieutenants present at the briefing given to the night shift by Captain Gibraltar about the events of the Best Young Flyers competition. Later, he and his squad defended the Rich family and several other celebrities at the Alicorn's Star hotel during "Operation Whirlwind", capturing Agent Deceit and saving the hotel's high-class occupants. Pursuing the escapees of Deceit's attack, he runs into and assumes command of the loyalists chasing the retreating main rebel force, leading the charge that ultimately forced the rebels to flee the city and freeing their hostages. (Rainboom Revolution)
Vesper was an unwitting victim of Lieutenant Troilus' conspiracy to hold hostage the "Cutie Mark Crusaders", having been duped by forged documentation into giving Troilus protect duty of the suite the three fillies were staying in. It appears that his efforts leading the batponies hunting for the escaped Aten may have left him out of touch of what was happening in Canterlot and made him an easy target for the conspirators. (The Crusaders)
Lieutenant Vesper temporarily assumed command over the entire nightshift when Lieutenant Captain Shining Armor was suspended following the stadium riot during the Wonderbolt's attempt at giving a performance in Canterlot post-Operation Whirlwind. He again had temporary control while Shining Armor lead Operation Just Cause. (Phoenix Down, A Just Cause)
The command of the batpony Lieutenant became a prime target for the Changelings attempting to infiltrate Equestria, sending false orders that frustrated Princess Luna's intention for them to help fighting Discord and giving opportunity for latent mistrust to come to the surface. (The Day of Discord)
After Shining Armor officially replaced Gibraltar as Captain of the Canterlot Guard, Vesper was promoted to Lieutenant Captain - the first batpony to hold the position - to fill the vacancy Shining Armor was leaving behind. He was also seen as the bat pony representative acknowledging Shining Armor as Captain of the Guard during the "passing the torch" ceremony. (Zero Point)

Lieutenant Aldebaran (Headcanon Voice: Michael Daingerfield) - Pegasus officer, most experienced one on the Canterlot night shift. He spent most of the early days of Shining Armor's new night shift command training him and others shuffled into an expanded night shift, and hence could not join Shining's efforts to help Luna's rehabilitation directly until the formation of the Royal Guard Oubliettes and Ogres club, of which he was a founding member.
The night shift devotion turned out to be quite personal: his grandparents - Emerald Wishes and Winter Blossom - were "believers" in Luna like the Thestrals, as was his father, who lead the night shift for most of his career. Aldebaran begged Luna to visit his still alive but frail grandparents before they passed on. Luna agreed to this request and eventually agreed to fulfill the promise. (Welcome Home, Princess Luna*,Operation Shield)
The squad under his command assisted in the search for Moon Dancer and later found Star Dancer after she had been dumped onto the mountainside of Canterlot following her horn removal. Aldebaran had Star Dancer brought to Canterlot General Hospital, which probably saved her life, and later received commendations for his bravery and determination. (Broken Fences)
Lieutenant Captain Shining Armor ordered Lieutenant Skyver to fetch two ponies in Aldebaran's patrol squad to replace the ponies posted at the gate after the assassination attempt on Buck Withers. Later, Aldebaran himself is seen as part of the Oubliettes and Ogres group founded by Shining Armor. After that, the LARP group he was a part of was attacked by "Mr. Hoofer", apparently in direct retribution for the thwarting of a previous attack. (Pocketful of Posies, In Praise of Twilight, High Fashion High Noon)
Aldebaran was one of the Lieutenants present at the briefing given to the night shift by Captain Gibraltar about the events of the Best Young Flyers competition. He was left in charge of castle security the night "Operation Whirlwind" was executed and found himself dealing with the machinations of Agents Snake and Sadness on his own, unable to stop them from infiltrating the castle and killing ponies until Aldebaran was reinforced by a party lead by Princess Luna. After the reinforcement, Aldebaran assisted in defeating Agent Snake in the castle's throne room. (Rainboom Revolution)
He briefly appears as part of the Canterlot Oubliettes and Ogres group in The Crusaders and Phoenix Down, the latter of which revealing the general persecution by Lieutenant Troilus of pegasi that had not joined Aten's rebellion.
He also briefly appears in Zero Point, relaying concerns to Shining Armor about the promotions of a batpony and griffon to positions of authority in the E.U.P. Guard.
* Canon in "broad strokes" only and characters used with permission of original author.

Lieutenant Crispin - Earth pony stallion and ranking member of the Royal Guard living in Ponyville. He is a member of the Apple clan, albeit through a "branch line" headed by Goldie Delicious (his grandmother) instead of the "trunk line" headed by Granny Smith. Crispin served as one of the worksquad leaders, then took command of the full operation when Fidelitas and Lieutenant Steelwing returned to Canterlot after foundational work had been completed. (Operation Shield)
He was tasked with "Operation Integration" following first contact with Zecora, and attempted to carry it out but had to call for reinforcement after coming against intense opposition of the Agents of Chaos. (Zecora)
Crispin was kept very busy following the parasprite infestation of Ponyville, both in leading the recovery effort and testifying subsequently in the board of inquiry that followed. (The Parasprite Project)
Crispin was one of Mayor Mare's escorts during the latter's announcement of Celestia's cancellation of Nightmare Night festivities. During that time, Applejack commented on how Crispin didn't like wearing his fulldress uniform very much. (Circle of the Moon)
Crispin interviewed the Cake couple after Sugar Cube Corner had been vandalized as part of Operation Whirlwind, and later assisted the Element Bearers in chasing down the vandals - Agents of Chaos P1 and P2. (Rainboom Revolution)
Crispin was posted permanently to Canterlot shortly after the failure of Operation Whirlwind, relinquishing his quasi-independent command in Ponyville in the process. He was allowed to appoint his successor before the transfer, and chose Meadow Song as his successor. He also was involved in the funeral of P1 and P2, having brought the foals of those stallions from Canterlot to Ponyville. (Consequences)
Crispin temporarily resumed his previous command in Ponyville when Lieutenant Meadow Song and his command were dispatched to Appleloosa on Princess Celestia's orders. (Mission to Appleloosa)
Upon Crispin's next intended visit to Ponyville, he was given a confidential scroll intended to be delivered to Granny Smith. After "checking in" with two of the three ERS checkpoints on the way from Canterlot, he was ambushed by a pair of Changeling drones (causing the vital delivery to never be completed) and killed between the 2nd and 3rd checkpoints. One of the drones that killed him then "replaced" him and continued down the road to Ponyville. (Zero Point)
Once in Ponyville, the drone that had "replaced" Crispin immediately began taking measures to secure a supply of love and advance further Changeling infiltration into Equestria, noticed as "odd behavior" by Twilight Sparkle, Applejack and Rarity (among others). A cover for this behavior was discovered thanks to a Twilight Sparkle "freakout", which gave the drone the idea of making her the "patient zero" of a behavioral disease to explain the changes. (Lesson Zero, Zero Point)

Lieutenant Excelsior (Headcanon Voice: Michael Dorn) - Male griffon, formerly a slave to the Griffon Ambassador. After suffering severely as a result of his slavery and abuse (including his wings being broken repeatedly, leaving them useless as a result), he was poisoned as part of a plot to abduct Princess Luna masterminded by both Agent Snake and the Griffon Ambassador. The poisoning apparently lead to his formal defection to the Equestrian empire and the exposure of the plot, which was defeated by Royal Guard officers. After the defeat of the plot, Princess Celestia administered "the Way of the Phoenix" to regenerate his ravaged and poisoned body, changing him from a weakened and grounded slave to a majestic warrior. On Celestia's command, he was formally inducted as a citizen of Equestria and given a provisional Guard Upper Class ranking. He was also placed under Lieutenant Vesper's command in the night shift commanded by Lieutenant Captain Shining Armor. (Excelsior)
Excelsior was mentioned, unnamed, in a letter Guard Lower Class Buck Withers sent to Lemony Gems. By the time of "Operation Shield", Excelsior had been trained enough (Lieutenant Vesper called him a "natural" flyer) to be enrolled into full service (Buck Nothing, Operation Shield)
He was first seen in full Guard service as part of Vesper's squad searching for Moon Dancer. Later, he was reluctantly persuaded to be involved in the play "Circle of the Moon", both as the main narrator and (in costume) as the manticore Manny Roar - we also learn that he had hoped to be assigned the liaison to Griffonstone in place of Prince Blueblood. (Broken Fences, Circle of the Moon)
He was involved in the Royal Guard Hearth's Warming party that was attacked by Agent Snake, attempting but failing to stop Snake from escaping via the air. (A Hearth's Warming Caper)
As part of Lieutenant Vesper's squad, he helped defend the Rich family, and later other occupants, at the Alicorn's Star hotel during "Operation Whirlwind", and probably joined the later counterattack, although he does not appear specifically at that time. (Rainboom Revolution)
Excelsior was selected to serve under Lieutenant Vigil as part of Operation Just Cause. After Lieutenant Vigil's squad was ambushed near the rebel-held "Fort Beta" during a scouting mission, Excelsior ended up being the ranking survivor of the squad. Shining Armor gave him an Acting Lieutenant commission as a result, and served in this capacity for the remainder of the operation. (A Just Cause)
Excelsior was officially commissioned as a Lieutenant on the night shift - the first griffon to reach the rank in E.U.P. service - shortly after Shining Armor was appointed as Captain of the Guard. (Zero Point)

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Agents of Chaos - A shadowy organization within the Royal Guard that served as an "enemy within", secretly subverting and disrupting operations for the apparent purpose of generating chaos. Their exact number and reach was never fully known, although apparently they were a large and deeply embedded force at one point. After the failure of their grand scheme "Operation Whirlwind", the remaining membership retreated southwest from Canterlot and spent several months engaged in guerrilla rebellion against Equestrian authority, occupying and raiding from two abandoned forts. "Operation Just Cause" attacked both of those forts, dispersing and effectively destroying the organization as a whole, although individual members survived.

Agent Snake in the Grass/Agent 1 - (Headcanon Voice: Jason Marsden) Leader of the Agents of Chaos, civilian identity Lieutenant Captain Aten. He synthesized two different groups that wanted to destroy the current order - pegasi resenting apparent unicorn domination in society and the Royal Guard, and those who wanted to end the rule of the alicorns in chaos - into a very dangerous threat. Ultimately, he executed Operation Whirlwind in an attempt to generate chaos and summon "the chaotic one" to take over Equestria again. (The Luna Shift onward)
He has a "secret lair" in the mines underneath Canterlot, which acts as the unofficial HQ of the Agents of Chaos and where he directs all Agent operations. This secret lair also has trophy shelves displaying the horns (unicorns), wings (pegasi) or heads (earth ponies) of ponies killed by the Agents of Chaos, The lair also has unfilled trophy spaces marked out for the three alicorn princesses, Shining Armor, Twilight Sparkle, Captain Gibraltar and Lieutenant Captain Fidelitas. (Buck Nothing, Consequences)
We also learn he keeps a secret "herd" in the mines underneath Canterlot, where beautiful mares of all races are exploited for his perverse pleasures. A number of these mares died down in those mines before this "herd" was exposed. (Pocketful of Posies, Consequences)
By the time of Circle of the Moon, Snake had been forced by the attrition of the Agents of Chaos to become involved in the battle directly, and A Hearth Warming's Caper implies he is in a state similar to the one Trixie was in while under control of the Alicorn Amulet in Magic Duel, although how closely it mimics that situation is currently unknown.
The sonic rainboom performed by Rainbow Dash at the Best Young Flyers competition was interpreted by Snake as the sign of "the pegasus triumphant" he had long sought, and shortly after executed his Operation Whirlwind. (Sonic Rainboom, Rainboom Revolution)
Whirlwind, despite Snake's best efforts, failed in reviving "the chaotic one", and Snake was defeated in personal combat by Princess Celestia. His wings were burned off, as was part of his mane that was later shaved off. At that point, he was taken to Canterlot General Hospital where his burned wings were removed surgically, leaving only nubs where they once attached to his body, as well as kept imprisoned pending a certain death sentence. (Rainboom Revolution, Consequences)
While in the hospital, however, he was visited by Agent X, who had de facto assumed command of the remaining Agents of Chaos with the objective of getting Snake out of the city. X and his deep-embed "partner" revealed their true Changeling nature to Snake while helping him escape - the first time the two races had interacted outside of disguise. (Consequences, A Canterlot Wedding)
More about Aten/Snake's rise to power is mentioned in The Crusaders, including that most of his future "lackeys" had lied under oath, coupled with forged paperwork, to enable Aten's rise to becoming a Lieutenant Captain in the Royal Guard.
After the events of Consequences, Aten was bailed out of Canterlot by his two Changeling Agents, regaining command of what was left of the Agents of Chaos and conducting a guerrilla campaign against ponies travelling along the Canterlot-Las Pegasus road during the time of The Crusaders to A Just Cause. This was helped by the deceptions of his two Changeling allies, which kept the loyalists distracted and brought several high-value prisoners to Aten.
A changeling duplicate of Aten was seen in A Just Cause, explaining to the Operation Just Cause forces the deception of the two Changeling Agents of Chaos. The real Aten was seen shortly afterward, planning the "last stand" of his remaining forces at "Fort Alpha" before fleeing southward to seek asylum at the Changeling hive under rule of Queen Chrysalis.

Agents P1 and P2 - A pair of pegasi stallions (P1 is white coated and P2 is dark coated) that were assigned jointly to Ponyville by Agent Snake. Either of their previous designations or their civilian identities are not known. The two Agents were tasked by Snake to distract Twilight Sparkle and the other Element Bearers, as well as the members of the town government, from interfering with affairs in Canterlot. As a result they were the indirect cause of many of the ills that befell Ponyville during the time of the canon show's Season 1. (Games We Play)
Both these stallions feature prominently in Operation Shield, first in discussing recruiting Trixie Lulamoon to the Agents of Chaos ranks, then in planning and executing several failed efforts to stop "Operation Shield". We also see their hideout, a small ruin in the Everfree Forest they named "Fort Chaos" after occupying it.
Agents P1 and P2 later assisted Agent 21 in an attack on the Ponyville jewelry shop owned by Lemony Gems, also covering his escape to Canterlot. It was also revealed their "Operation Smoky Mountain" was the immediate cause of the problematic sleeping dragon near Ponyville which Fluttershy was able to convince to move elsewhere (Dragonshy, Pocketful of Posies)
These Agents were later tasked with stopping "Operation Integration". Initially successful in their disruptions, they failed to stop the reinforcements sent from Canterlot to finish the mission and ultimately became affected by poison joke, making further operations very difficult to execute. (Zecora)
Despite being trapped in the Everfree Forest as a result of the poison joke affliction, the two Agents were still able to cause chaos by being the initial trigger for the parasprite infestation by releasing the initial parasprite to Fluttershy's attention. Later, they helped spread the parasprites to Canterlot by linking up with Agent X. (The Parasprite Project)
They later made a contract with "The Pony of Shadows" to continue their work and remove the poison joke effects, attacking Carousel Boutique and destroying costumes intended for the batponies while apparently possessed/manipulated by the aforementioned entity. This did not result in a cure of their poison joke affliction, however. (Circle of the Moon)
During Operation Whirlwind, the two Agents snuck into Ponyville in "alicorn" disguises, vandalizing Sugar Cube Corner and abducting Rainbow Dash. Rainbow's fellow Element Bearers chased after them and set Rainbow free, causing the two Agents to ditch their disguises and flee back into the Everfree Forest. The Element Bearers and an allied group of ponies chased them to their hideout, where after a short battle both stallions were killed when Rainbow Dash "nuked" Fort Chaos. (Rainboom Revolution)
The bodies of Agents P1 and P2 were retrieved from the ruins of Fort Chaos and given civilian burials jointly - their treachery had voided any military honors they would've otherwise received. The short joint funeral was attended by the Element Bearers and the foals of the two Agents, among other ponies. (Consequences)