Consider

First strike When Gerrard dies, exile it and return to the battlefield all artifact and creature cards in your graveyard that were put there from the battlefield this turn.

Karn's power and toughness are each equal to the greatest mana value among artifacts you control. At the beginning of your upkeep, add C for each artifact you control. This mana can't be spent to cast nonartifact spells. Until end of turn, you don't lose this mana as steps and phases end.

Flash 1, Sacrifice this creature: Destroy target artifact or enchantment.

You control target player during that player's next turn. Exile Worst Fears. (You see all cards that player could see and make all decisions for them.)

Search your library for a basic land card, reveal it, put it into your hand, then shuffle this spell into its owner's library transformed. (For playtesting purposes, put it into its sleeve upside down.)

+1: Draw a card. At the beginning of the next end step, untap up to two lands. −3: Put target nonland permanent into its owner's library third from the top. −8: You get an emblem with "Whenever you draw a card, exile target permanent an opponent controls."

Hosted creatures get +2/+0 and have haste. Host 1R (1R: Host target creature at this Realm. A Realm can host any number of creatures. Host only as a sorcery.)

All artifacts have "At the beginning of your upkeep, sacrifice this artifact unless you pay 2."