Get the MID planeswalker to eight loyalty counters and its controller can return all permanents to hand without a hand size limitation, potentially ending the game within specific deck builds
Once it makes its way onto the board it is a virtually unstoppable infecting, indestructible machine.
Eron was cool for being a big hasty beater that could be made to survive rough blocks while Autumn Willow had one of the earliest versions of hexproof in the game
It works well with aggressive extra combat commanders like Otharri, Suns' Glory and Isshin, Two Heavens as One, and is notable for giving you an additional main phase along with your extra combat
And whenever one or more cards are milled, we can put a +1/+1 counter on as many creatures as nonland cards that were milled
My personal favorite is from Unfinity , but you can find a thousand great tokens available online from independent artists