There are lots of 0-mana artifacts in the game, like Moxen and Lotus Petal, even Memnite and Ornithopter
Otherwise, there arent too many surprises here, though the one guy who probably has an entire box of all the lace cards keeps making his presence known
Though typically known for being yellow, they are found in different colors throughout the Final Fantasy games
As Mark Rosewater recently explained in their Q&A Blogatog, you dont have to play five colors to make domain cards viable in Limited. Instead, Domain can often be seen as an added benefit to many cards that scale with your land base
To get around this problem, which can occur against any deck, just most readily versus RDW, Necro based decks will pack a lot of life gain abilities