Yu-Gi-Oh! Nightmare Troubadour: Beginner Puzzle 11

Beginner #11 Blueprint For Revenge -- Activate Shield & Sword.

Activate Polymerization and select Gaia the Dragon Champion by discarding Gaia the Fierce Knight and Curse of Dragon and select attack position.

Switch to Battle Phase.

Attack Blue-Eyes White Dragon with Gemini Elf.

Activate Time Machine.

Attack Blue-Eyes White Dragon with Gaia the Dragon Champion.

Attack opponent's life points with Gemini Elf.