Gate to Phyrexia, Chaos Warp, Tithe, and other ways colors get to do things they ordinarily can't make it easier to build decks exclusively using that color
(2026-01-27) You can't activate an ability that advances a Class to a particular level if that Class is already that level or higher
The Sacrifice Package Now this is where the engine revs up
Killing it is no good, seeing as it returns to the battlefield and draws a card when it dies, making opposing removal spell look useless
Swiping two good cards (the third and fourth best in the deck) makes for good card draw, assuming you have the colors to cast opposing spells
By far the weirdest activated ability I know of is Lightning Storm, the card that used to be the win condition in Modern Ad Nauseam decks