Several decent Darkness-type decks will get the job done at low rarity, and have the benefit of also clearing the Knock out Pokmon using attacks from a Darkness-type Pokmon challenge present in some of these battles
Karn, Silver Golem Everybodys favorite golem, Karn gets their spark and a few Cube staple planeswalker cards
At $1, it provides selective card advantage that often locates your game-winning ACE SPEC
Sometimes it doesnt even have to make sense some boss monsters will wind up belonging to archetypes that have nothing to do with Light only for the boss itself to become a Light based monster
Then the other ability triggers when you cast a noncreature spell from exile, like from his first ability or Adventures, suspend, foretell and more
Your sideboard can now include absolute bombs like Ugin, the Spirit Dragon, or a much-needed Farewell to ensure your victory