It's a little weak against Blue decks as they have the option to spend a Blue mana to deal no combat damage when it swings
Duskwatch Recruiter // Krallenhorde Howler
Legendary Creature - Rat Ninja Tasha, the Witch Queen Whenever you cast a spell you don't own, create a 3/3 black Demon creature token
As pointed out in the comments, its important to remember that The Coffin only gives you protection from everything, not your bits and baubles, in an Indiana Jones hiding in a fridge sort of way
Chaos: Whenever you roll Chaos, each player discards their hand, then draws seven cards
I do think this is an absolutely A+ carrier for artifact/equipment decks, especially since it can help enable things that synergize with historic cards in equipment heavy strategies too