So, if youve had Mystic Remora for three turns now, you have to pay three mana at your next upkeep
Recently I cataloged them by color to make sure I covered all the bases
Temple Bell is of course extra nice if you can untap it at will
Here are the pull rates for the most expensive cards in the Standard-legal set
In general, I think such Gimmick decks can be built with the following parameters: 11-16 Lands 9-16 copies of Card A (Hero, Rat, Elves etc.) 4-8 copies of Card B (Dark Ritual, Crusade, Giant Growth) Remaining cards are miscellaneous inclusions or singletons
Looping creatures with this is incredibly easy to do, and whats more, its hard to interact with, given returning it to hand is a cost rather than part of the ability resolving