I think I got the solution.
Warsong Commander -> Frothing Berserker -> Fiery War Axe -> 2x Dread Corsair (free from War Axe) -> Whirlwind
Your opponent's board should look like this:
Sludge Belcher 3/4
And yours should look like this:
Grim Patron 3/1
Grim Patron 3/1
Grim Patron 3/3
Warson Commander 2/2 (can't attack)
Dread Corsair 3/2
Dread Corsair 3/2
Frothing Berserker (9/3)
Fiery War Axe
2 mana left
Trade both Corsairs into Belcher, then the 3/3 patron into the Slime, gaining another 3/3 Patron.
Your board:
Grim Patron 3/1
Grim Patron 3/1
Grim Patron 3/2 (Already Attacked)
Grim Patron 3/3
Warson Commander 2/2 (can't attack)
Frothing Berserker (15/3)
Fiery War Axe (3/2)
Slam your 3/3 Grim Patron, gaining another Patron and boosting your Berserker by 1 attack.
Your board:
Grim Patron 3/1
Grim Patron 3/1
Grim Patron 3/2 (Already Attacked)
Grim Patron 3/1 (slammed)
Grim Patron 3/3
Warson Commander 2/2 (can't attack)
Frothing Berserker (16/3)
Fiery War Axe (3/2)
4X3 attack Grim Patrons + 16 Attack Berserker + 3 attack Fiery war axe = 12 + 16 + 3 = 31