Sakashima the Impostor [Mystery Booster] SM164 but I believe a more

but I believe a more mundane power source might suffice

Set: EX: Legend Maker Type: Fire Rarity: Common Retreat cost: Colorless

{1}{W}: Another target creature gains lifelink until end of turn

Whenever a Mountain is tapped for mana

Sakashima the Impostor [Mystery Booster] SM164 but I believe a moreSet: Mystery Booster Type: Legendary Creature Human Rogue Rarity: Rare Cost: {2}{U}{U} You may have Sakashima the Impostor enter the battlefield as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return this creature to its owner's hand at the beginning of the next end step."