Thunder Dragon + Giant Turtle Who Feeds on Flames → Kairyu-shin

Thunder Dragon + Rose Spectre of Dunn → B. Dragon Jungle King

Thunder Dragon + Ghoul with an Appetite → Skelgon

Thunder Dragon + Violent Rain → Kairyu-shin

Thunder Dragon + Penguin Soldier → Kairyu-shin

Thunder Dragon + Fairy Dragon → Twin-headed Thunder Dragon

Thunder Dragon + Liquid Beast → Kairyu-shin

Thunder Dragon + Twin Long Rods #2 → Kairyu-shin

Thunder Dragon + Electric Lizard → Twin-headed Thunder Dragon

Thunder Dragon + Lady of Faith → Kaminari Attack

Thunder Dragon + Armored Starfish → Kairyu-shin

Thunder Dragon + Rock Spirit → Kaminari Attack