Shift allows the four cost card to be deployed for only three ink, Evasive makes him difficult to challenge, and Challenger +3 gives him a boost when he's on the attack
A new card type, inspired by Final Fantasy summons like Shiva, enters the game with a lore counter, gives an instant effect, and stays for a few turns before vanishing, copying the short but strong nature of summons
I'm not much of a red or white player, but I can't deny that Lightning, Army of One has the potential to be broken in most formats
You may even want to do that yourself: If you keep removing Summon: Fenrirs first lore counter with your Glissa Sunslayer or Power Conduit, Fenrir's first chapter will keep triggering on your turn, and you'll keep ramping up