His metal arm with a claw was inspired by Diesel 10 from Thomas and Friends. The reason he has it is because when he was getting beaten up as a lowercase kid for "spelling" the bad word, one of the letters ripped off his top part, and after he exiled himself to his cave, he began working on a prosthetic arm with a claw to replace his top part.
Credits to @PhonicLover44, @AlfabetonsOfficial, and @amtrakman4014 for the sprites! Credits to Mike Salcedo for Alphabet Lore!