mtg banding cards questions : r/magicTCG Bands are blocked as a group What Is Banding in Magic:

Magic Adds Four Cards To Commander Ban List Magic: The Gatherings Commander format got a major shake-up earlier this week with the announcement that the Commander Rules Committee was adding four powerful cards to the ban list

And Sephiroth is a mythic rare, the highest rarity card

Legendary Creature - Nightmare Sorin, Imperious Bloodlord +1: Target creature you control gains deathtouch and lifelink until end of turn

For a Challenge-focused deck like this, Resist can make a huge difference

Narcomoeba: A small, but evasive creature, Narcomoeba can enter the battlefield if it was put into your graveyard from your library