F: Equivalent of H. Debuts in Ê's episode. J: I's older sister who also gets used as a cannon before being rescued in Q's episode, later joining the heroes. Debuts in I's episode. W: An evil alien created by Ê that can shoot laser beams out of his eyes. Debuts in V's episode. Z: An angel who debuts in the second epilogue. After the flashback is finished, the question mark summons Z, who heals the injured letters and revives the dead ones. He also knows about Ê's backstory and will help him to become nicer.
Credits to: @PhonicLover44 @wario100 @AlfabetonsOfficial