rikku mtg card Full Art - 16-137S - Emissaries of Light until end of turn Rikku Resourceful Guardian | Final

The key thing to understand about Omega, Heartless Evolution is that its text regarding non-basic lands really means Towns, as thats what all of the non-basic lands in the set are

With proliferation and permanents like Geometric Nexus, you should have a sinfully good time

Like many other effects, this lasts as long as the card is on the battlefield, but the cool part is that once its removed, the effect doesnt end until the end of the turn

Overall, Mayhem is a much worse version of Madness, but it can still be incredibly valuable, turning discard costs to other abilities into straight value

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