Until about 200 years ago, when an arctic exploration team came across a miraculous discovery, a frozen young twonicorn colt(who had a pale-colored coat, the body figure of a 4 to 5 year old foal, had two different colored eyes, one sky blue & one neon green, and didn't even have his cutie mark yet), perfectly preserved deep in the arctic ice for who knows how long, the twonicorn colt was then brought back to the mainland, where he was thawed out, then a reanimation spell was used to awaken him, for whatever reason that he was frozen alive for an unknown amount of time, the twonicorn colt lost all of his memories, he could not remember where he came from, who is family was, or how he got frozen in the first place, he couldn't even recall his own name, all he could remember was that he was a Twonicorn, unfortunately it seemed that he was the Last Twonicorn.
The twonicorn colt was later brought before the Cosmic Council(as mentioned in the MLP storybook Under the Sparkling Sea, which I assume is similar to the United Nations in the real world), myself included, to decide what should be done about him, since he was perhaps the only twonicorn left in the world, we all knew that as long as at least 1 of them was still around, there would still be hope of defeating Grogar the next time Tambelon would return, unfortunately seeing as how impossible threats were already at an all time high, matters had to be taken immediately if not sooner, it was decided by the Council that the young twonicorn had to become combat ready as soon as possible, the Council decided that to help speed up the process, his teachers would have to give private sessions with him, he was to be forbidden from all forms of childish distractions, to be isolated from normal society, never allowed to interact with every-day ordinary civilians, cut off from all attachments of friendship, love or emotions, to focus solely on becoming a strong force against evil, naturally I was against that decision, but my objection was majority overruled.
Since then the twonicorn colt was sent all over the world, being forced to train in every known form of the mystic arts, the martial arts, and weapons handling, being trained by the greatest masters in the world including myself, and since he was a twonicorn he could not only perform all of these forms of magic exceptionally well, but could take them to levels we didn't even know were possible, presumably because we still knew very little of what Twonicorn Magic was truly capable of, once he even showed me that he learned how to control the Sun & the Moon from just watching me do it, though he was able to control them even faster & better than I ever could by myself, he was even able to perform various tricks with them, naturally I got on him about that, telling him not to do things like that because I had to maintain order within my responsibilities, but I did admit that I was seriously impressed that someone so young could have such power, making me realize that there was a lot more to a twonicorn's true potential than I could ever even imagine.
All day everyday, the young twonicorn did nothing but eat, train, sleep, train, bathe, and train some more, often times he was disciplined for not taking his training seriously, or getting distracted for childish things, it was a lot of pressure to put on one so young, but being the last of the Twonicorns brought him a lot of burdens & responsibilities that he never even asked for, but given the circumstances he had no other choice, though I did try my best to become the closest thing he would've had to a friend, but I was only allowed to go so far based on the Council's decision, that little colt went through a lot of Psychologically Traumatic events that no foal should ever have to experience.
During his weapons training he proved to be very adapt to sword wielding, when he later received his cutie mark, it was a Coat of Arms made of a set of swords, after that happened I suggested to the Council that we start addressing the twonicorn colt as "Claymore" because of his connections to swords, the Council agreed and from then on the colt was named Claymore, all of his training & psychological traumas lead to him developing certain emotional instabilities, such as excessive rage, unnecessary hostility, and severe A-social traits, but conclusively most of the Council thought that it was all worth it, for he had also became a hard-boiled, fearless, tough as nails combatant, ready to take down anything that got in his way, ultimately Claymore had become the very thing I wished to have prevented him from ending up as, A Living Weapon.
When he reached his later teens, we used the Twonicorn's magic forge to smith a special set of weapons & gear made specifically for him, which included a pair of double-edged swords, a set of 3 dozen Hira-shuriken throwing stars, a special chain that can only be unlinked through powerful enough magic, and his own set of horseshoes & body armor, all made using a perfect mixture of iron, silver & dragon's tooth(because dragons can chew diamonds, it's safe to assume that dragon teeth are the hardest known substance in the pony world) to not only guarantee that they would be able to dispel Supernatural/Paranormal forces, but so they would also be unbreakable,(now the swords themselves look like a pair of Double-Edged Chinese Jian/Japanese Tsurugi/Korean Geom Straight Swords, other than being indestructible & deadly to Supernatural/Paranormal creatures, they're not all that special, but in Claymore's possession he can channel his Twonicorn Magic through them to light them up like Star Wars style light-sabers with just as powerful slashes, and can swipe them to unleash destructively powerful energy waves similar to Kirby/Meta Knight's sword-beams from the Kirby video game franchise, or Optimus Prime's Star-Saber/Megatron's Dark Star-Saber from Transformers Prime, so don't underestimate this Steed's swords).
Since then Claymore became one of our world's greatest warriors, and because he's the last of the Twonicorns, he's often been called "The Most Powerful Equine in the World", who traveled all across the globe protecting us from evil forces that threatened to concur or destroy us all, many of the world leaders, myself included, gave him special legal immunities to help make his missions less complicated, and would often establish cover-ups with his involvement in whatever situation for his own protection, he was even taught how to use the Age spell, to keep himself young & vital so that no matter how old he got, he would always remain at the top of his game, which he will need to be at for when Tambelon makes it's return, so he will be able to face-off against Grogar.
Then the holo-display ends and the tablet deactivates, thus concluding the Narrations by Celestia.