Mardu Energy is a fast, wide aggro deck that threatens to bury you under tokens from Ocelot Pride and Guide of Souls while pivoting to a Goblin Bombardment sacrifice finisher to punch through your blockers. Wrath of the Skies is your most important sideboard card — it resets their board at a flexible cost and invalidates their go-wide gameplan entirely. Boromir, Warden of the Tower is critical for shutting off Goblin Bombardment's sacrifice trigger, which is otherwise nearly impossible to interact with at instant speed. Fatal Push, Solitude, Prismatic Ending, and Ephemerate remain central — use Ephemerate on Solitude or Overlord of the Balemurk to generate card advantage while keeping the board clean. Cut Teferi (too slow against their curve and doesn't impact their threats) and the lower-value one-ofs in favor of your sweepers and hate pieces.