green storm cards mtg the Seedcore - March of the Machine - another target attacking creature gains flying and gets +X/+0 Historic - Mono Green Storm

Prosper, from the accompanying Commander decks, is an interesting case, because it is the first time they tried to find synergies for the mechanic

It also works with creatures, which means you can either have a free board or play a turn ahead of everyone else

Honorable Mentions Nicanzil, Current ConductorNicanzil, Current Conductor Lord of AtlantisLord of Atlantis/Master of the Pearl TridentMaster of the Pearl Trident Thieving SkydiverThieving Skydiver Thieving Skydiver Seafloor OracleSeafloor Oracle Seafloor Oracle Deeproot HistorianDeeproot Historian Deeproot Historian Top 21 Merfolk Cards for Commander 21

Mirri, Weatherlight Duelist To counteract the somewhat fragile nature of the cat-mander deck, Mirri, Weatherlight Duelist, is a Commander that nullifies your opponents creatures

You can also always choose fewer than four copies of the card to exile, even if there are more in the deck