Mana Geyser I remember the first time Mana Geyser was played against me in a game of Commander
Its a must-have for aggressive rainbow builds, which are admittedly few and far between
Depending on whether someones purpose is to buy cards, speculate on certain card values, or build a deck, the answer to the question Which card game is worth the most money
Ayula, Queen Among Bears Heres an example list from a Modern Horizons draft a friend of mine (Slatorade) did: The only spells in this pile of 36 Forests are Ayula's Influence (all lands can be instant, 0-mana 2/2 bears), Ayula, Queen Among Bears herself (2/2 for one green that rewards you for putting bears into play), and two Winding Ways which would almost always draw four Forests
It's one of the strongest Izzet commanders ever printed thanks to generating ridiculous amount of mana and looping spells for game-winning combos
Sure, if this stays in play for three or so turns then it is going to dominate the game but lots of cards fit that bill