cards that end the turn mtg (Glorious) of Amonkhet: Exclusive Preview End the Turn MTG –

Plenty of Otters have the prowess ability, turning your spells into overwhelming advantages in combat

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They're also cumulative with other effects that let you play additional lands, such as the one from Urban Evolution

While my deck does not run much black, I need access to black mana to cast Kess

Its drawback may look like its very punishing and can allow the opponent to surprise you via a mid-combat spell, but I never really saw that scenario play out since its damage prevention ability is a a conditional static ability so as long as its on when damage is dealt, it wont be prevented. (Thank you, @fenaris!) It usually plays out somewhat like a colorless Ashenmoor Gouger / Chimeric Idol where you typically dont bother trying to block with it (why am I blocking with my aggro guys anyway?) and, if need be, you cast a spell pre-combat to activate it (typically I used a large coin, like a quarter, to denote whether it was on or off)