Mass of Mysteries

Myriad is a keyword built around attacking into multiple opponents: a way to give attackers reach that scales with how many opponents you face, spawning tapped-and-attacking copies at each of them and cleaning up the tokens before they overstay their welcome. What this Elemental adds is the ability to hand that keyword to a creature that was never printed with it. At the beginning of combat, it grants myriad to another Elemental you control, meaning any beater in the tribe becomes a source of copies for a single swing. The design puts the keyword on the wrong noun on purpose: instead of a myriad creature that copies itself, you get a myriad enabler that turns your best Elemental into the multiplier, then repeats the grant each combat on your turn. The five-color identity is doing real work here, opening the pool of eligible bodies well past any single-color Elemental deck, and the printed body backs the plan: first strike, vigilance, and trample on a 5/5 means it can both grant the keyword and keep swinging into a full board without tapping down. The catch that keeps it from being a pure engine is targeting, since the grant needs another Elemental to point at; a lone commander does nothing but attack as a well-statted 5/5. Build a wide enough tribe and it turns one attack step into a fork aimed at every opponent at once.