The Warring Triad* A very interesting take on a 3 mana rock that helps you advance your general gameplan until Kefka gets in the way (represented by 8 or more cards in the graveyard) and then it unleashes plenty of power
If you're cool with stripping your opponent of all their gameplay options (which, granted, sounds a lot harsher than it actually is), a WaitWin will soon be yours
Realistically, I think a Naya Enchantments build running Terra and Yenna is the way to go for this combo in Standard
This card is obviously good with any commander that has green in their color identity, but you can also use it to cast any legendary spell and prevent it from being countered
This is not a vehicle format, and even if it was, this is too expensive and narrow to be worth playing
I think Id rather have Doom Engine most of the time, honestly