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It doesnt just triple the mana you make with your Lands, as any of your mana rocks also tap for additional mana, too

Inferno of the Star Mounts ( F, C ) - There a few ways to increase its power, and that is by comboing it Thrakkus the Butcher - Activate it 3 times, attack, and then activate it another two times, an you deal 20 damage for 5 mana

Then put all cards exiled this way that weren't cast on the bottom of your library in a random order." A spell's mana value is determined only by its mana cost

Then this Temur Elemental Horror will double your ETB triggers of stuff you control, so it's a Panharmonicon for all of your stuff

But you can mitigate this with the protection and recursion slivers in the rest of the deck