Song of the Worldsoul

Populate is normally a one-shot rider: a keyword stapled to a spell or a convoke trigger that copies a single token and moves on. Here it is decoupled from any specific spell and welded to the act of casting itself. Every spell you cast, of any type, at any cost, fires the trigger, which means the enchantment sits inert on arrival and starts paying only once you have already assembled the token board it feeds on. That dependency is the honest tax on the effect: populate copies a creature token you control, so an empty battlefield returns nothing, and a battlefield holding a single Angel or a stack of Saprolings turns each cantrip into a compounding army. The design rewards a deck that front-loads token production and then floods the stack, and it punishes the durdle who resolves the enchantment expecting immediate value. The ceiling is set entirely by the quality of the token underneath it: populate copies the best token you control, so whatever you managed to put into play once, not the enchantment's own rate, dictates how fast the board balloons. It asks for a token generator on the table before a grip full of spells becomes lethal, and it repays that setup with a trigger that never stops as long as you keep spending mana. This is the token engine that arrives late and then refuses to quit.