Mardu Energy pressures with explosive early threats like Ragavan and Guide of Souls, then post-board introduces Fulminator Mage to destroy bounce lands before Amulet of Vigor is active and Thoughtseize to strip combo pieces from your hand. Vexing Bauble taxes Thoughtseize and Galvanic Discharge, buying critical turns to assemble your engine. Dismember answers Ragavan on turn 1 and Fulminator Mage before it can attack your mana base. Engineered Explosives at 0 clears Ocelot Pride tokens and at 1 hits most of their one-drops. Ensnaring Bridge — fetchable via Urza's Saga or Karn, the Great Creator — is the key trump: once you've deployed your hand setting up Primeval Titan, they cannot attack through it, so prioritize a turn 3-4 Titan kill before their board snowballs out of control.