Behind the Curtain: Lateral Movement chapter 125 · 2:56am Jul 17th, 2017
Just to be absolutely clear, this will contain spoilers for the chapter mentioned in this blog post's title.
I've been quite forward about the fact that many of the characters in Lateral Movement, particularly Lex and Sonata, have their powers and abilities represented via RPG stats under the d20 System, the game engine upon which Dungeons & Dragons Third Edition and Pathfinder, are built.
Doing this helps me to ground their abilities, keeping a firm grasp on what they can and cannot do so that I can better represent them over the course of the story. While numerous supporting characters are drawn from various bestiaries and supplements (often with some minor tweaking), Lex and Sonata have custom-built stat blocks (made with my favorite supplement, Eclipse: The Codex Persona), both of which can be found on my other blog (indeed, I posted here when I made stats for Sonata).
Lex's stats, which can be found over here, represent his powers and abilities as of the events of chapter 45...mostly. There are several discrepancies between what's in that blog post and what's to be found in the story (due to my having put the story on hiatus when I wrote that blog post, and only having a rough idea of precisely how things would subsequently progress), but what's there is generally correct, at least insofar as you won't find Lex using any powers that aren't accounted for in there during the story.
Which brings us to chapter 125, "The Horn of King Sombra."
In this chapter, Lex has had his horn - the Horn of King Sombra, represented in his stat block as a relic - cut off, only to regrow a moment later (with the severed horn turning into black crystals). However, there's nothing in his stat block to represent any such thing. Rather, it says only that the Horn is a relic which Lex has attached to himself, gaining its powers. So what's going on here?
The answer is quite simple: Lex has gained a level, and this is a consequence of that.
As I noted on my first design diary, Lex was originally written to be a 4th-level character, who was advanced to 8th level to keep pace with the characters of David Silver's A Dangerous Sparkle. As of his appearance in The Apple Falls Far from the Tree, he had advanced to 9th level, where he remained until chapter 45 of Lateral Movement, "Divine Prerogative." At that point, the Night Mare granted him a template worth another two levels (in other words, a +2 Effective Character Level template), making him effectively level 11. Now, eighty chapters later, Lex has finally gained another level, making him level 10 with a +2 ECL template, or effectively level 12.
How did he do that? Well, I'm glad you asked. 
The first thing to note is that Lex's advancement is measured on the "fast" track of the Pathfinder RPG experience tables. This is because he's typically either going it alone, or with only Sonata by his side, rather than being part of the standard four-person party. So as a 9th-level character, he had 50,000 XP (experience points) - the bare minimum for his level - when we saw him in The Apple Falls Far from the Tree.
When he gained that template from the Night Mare, it effectively made him an 11th-level character, but he didn't gain any additional XP for that. As such, in order to gain another level, he needed to gain sufficient experience points to become a 12th-level character; in other words, he needed to gain 95,000 XP in order to reach the 145,000 XP necessary to become a 12th-level character. So when did he do that?
The first major gain came from his battle with Moss (aka Vilzeralixus), which concluded in chapter 34, "What It Takes." Being an adult green dragon, Moss was worth 19,200 XP, all of which went to Lex for defeating him in single combat. While Lex did pick up a hooffull of other XP awards from other battles (most notably Lirtkra, Monitor, and the Cripple) and traps, the next major source of XP was his battle with Tlerekithres, the Great Lord of the Deep, which ended in chapter 105, "He Who Laughs Last." Lex defeated Tlerekithres in conjunction with Cloudbank (everypony else didn't count for that fight, as they didn't actually participate in the battle against Tlerekithres himself, instead fighting their own enemies), and so earned half of the XP award. Since a kraken is worth 153,600 XP, he received 76,800. Combined with the 19,200 XP he received from Moss, that's 96,000 XP, which is enough to put him over even without calculating the XP earned from his other fights. (Technically, Cloudbank earned that much as well, but she ran afoul of that pesky rule that says that if you gain enough XP to advance multiple levels at once, you only gain one, and the remaining XP is lost.)
So in other words, Lex actually leveled up back in chapter 105; we're just seeing some of the results of that now (since the results of gaining a level are supposed to be an organic advancement of a character's abilities over their adventures, rather than an instantaneous jump in power).
That brings us to the question of what exactly Lex earned from that level. Since he's built via Eclipse, he can purchase his abilities directly rather than following a class-based progression. Reaching 10th level grants him 27 Character Points (CPs) (24 for gaining a level, 1 for his restrictions against wearing armor, and now - starting at this level - 2 CPs for his duties as a ruler of two cities), which he has spent on the following:
- 1d4+3 hit points (0 CP).
- +1 BAB, corrupted for two-thirds cost/no iterative attacks (4 CP).
- Fort +0, Ref +1, Will +1 (6 CP).
- +6 skill points (Intelligence bonus), +1 skill point ("favored class" bonus), +1 skill point each for Knowledge (arcana), Knowledge (planes), Spellcraft, and Use Magic Device (Fast Learner and Adept) (0 CP).
- +1 sorcerer magic progression levels (Intelligence-based; arcane magic; components and restrained limitations), corrupted for two-thirds cost/must locate or invent new spells to be able to prepare them, specialized for one-half cost/can only replenish spell levels with Rite of Chi (4 CP).
- +1 caster levels, specialized for one-half cost/sorcerer progression only (3 CP).
- Immunity/relics cannot be damaged or removed (common/minor/great), specialized for one-half cost/only for the Horn of King Sombra, corrupted for two-thirds cost/may be removed if Lex is killed, petrified, or otherwise not alive (4 CP).
- 6 CP remaining (I won't say if these have been spent or not, yet).
And there you have it. The reason Lex's horn grew back is because he'd purchased an Immunity to it being removed from him (or damaged; any damage directed at it is simply dealt to him as per a normal hit). Cutting it off simply caused it to grow right back, the same way it did for King Sombra back in Return of the Crystal Empire - Part 2, unless he dies first (just like King Sombra). Of course, from a narrative standpoint Lex might have "always" had this Immunity, but in point of fact it was only recently acquired...and just in time, too!
I'm guessing seeing Sombra grow his horn back left a mark on Lex and despite the terrifying events around that moment, it proved to be a beneficial one since Lex could have purchased any other ability other than Immunity.
Wonder how Lex will spend his remaining CP, if he hasn't already.
*cringes at the point-buy cheesiness* Although to be fair, I did the same sort of thing when I was playing Champions. n.n
4603885 Aw, it's not that tricked out.
4603867 There's a meta-game implication with regards to the mechanics, as it's debatable how much the character spends the points involved, rather than the player (which in this case is me). Obviously, things like increasing his magical abilities are something he'd actively work towards, but the Immunity to losing his horn is more questionable (particularly since there's a case to be made that it should have been there from the beginning...especially since there's no way from a purely-narrative standpoint (that is to say, just from reading the story) to say that isn't the case).
Fortunately, it's something of a moot point now anyway.