Stiflenought wins by countering or Stifling the Dreadnought's triggered ability to get a free 12/12, then protecting it with Foil, Counterspell, and Daze while you can't attack through it. Your best line is to burn them out before Dreadnought lands, since your creatures can't block or race a 12/12 trampler. Bring in Red Elemental Blast and Pyroblast to fight through their counter suite and push through your burn spells in the late game. Goblin Cadets comes out because it becomes a liability — the opponent can force unfavorable attacks with a 12/12 trampler in play, and Cursed Scroll is too slow in a matchup where you need to close quickly before they stabilize. Prioritize fetching dual lands early to hit four mana for Fireblast, as that's often your most efficient route to lethal.