Stasis (Limited Edition Alpha, 1993) Appearing all the way back in the very first Magic set, Stasis has earned quite a reputation for grinding games to a halt
In other words: Clues are very good when you get them for free as part of doing something else (attacking with Azula, On the Hunt, playing lands with Tireless Tracker, casting creatures under Lonis, Cryptozoologist), and there are tons of cards that have synergy with tokens, artifacts, or sacrifice
I particularly like the latter because you'll have to keep drawing into lands with Wyleth's attack trigger if you want to keep the combat steps coming
This one comes to us from Heisen01, who pulled off a 5-0 with it in Tuesdays MTGO Pauper League
Giving you access to that mana as soon as you find it is incredibly powerful, and made the endless Evolving Wilds reprints we saw in sets after Throne of Eldraine feel a little underwhelming in comparison