Card Trivia:Watthydra
- This is the strongest Thunder-type "Watt" Monster, in terms of ATK and DEF Level. ("Wattaildragon" is strongest overall)
- This card's second effect is the same as that of "Gold Sarcophagus".
- This card's amount of heads is equal to its Level.
- In Greek mythology, the "Lernean Hydra" is an ancient serpent-like beast that possessed many heads. It was killed by Heracles as the second of his Twelve Labours.
- According to the legends and myths of the Nyanga (people who live in the Congo River region), "Kirimu" is a dragon described as "a huge animal with a black hide, seven heads, seven horns, seven eyes, teeth like a dog, a huge belly, and the tail of an eagle".
- It was said to have gone from the mountains into a village and ate a tribe of people. Later, when it was slain, the people were rescued from its stomach. This may be a reference to its effect; It goes to the deck to "eat" a card (remove it from play) and getting it back later on.
- "Watthydra" would seem like the "Watt" counterpart of "Chimeratech Overdragon" and "Yamata Dragon" artwork wise.
