Fortress Whale
Yu-Gi-Oh! archetype · 3 cards
Fortress WhaleTP7-EN003 · Tournament Pack 7 · +3 printings
Fortress Whale's OathTP7-EN011 · Tournament Pack 7 · +2 printings
Mega Fortress WhaleLED9-EN016 · Legendary Duelists: Duels From the Deep
Archetypes from YGOPRODeck and YAML Yugi (Yugipedia).