This sticking around enables a lot of nonsense with cards like Etali, Portal to Phyrexia, etc.

this is a very powerful card. in one of my commander decks I need a permanent of 7 mana and one of 5 mana + 2 to give it haste to instantly win the game, but with Tannuk in play I can pay a total of 6 to warp them both and win the game potentially by turn 4-5, so I win with 4+6 mana instead of 7+7. this is DEFINITELY going into my deck if the price doesn’t go up too much.

for anyone wondering, current combo win requires Gisela, blade of Goldnight (doubles the damage my opponent receive, halves the one I receive) and Heartless Hidetsugu (taps to deal damage to each player equals to half their life total, rounded up). haven’t pulled it off yet, since both pieces are usually KoS, and Tannuk might as well, but Tannuk definitely allows for a surprise win