Gargantua
The final warrior of Genome Kingdom, Gargantua is created by firing a vegetative graft into Homme-Du-Feu. The graft fuses Arduina and Homme-Du-Feu, giving birth to a giant bigger than the ZOTT arena and controlled by Homme-Du-Feu, but having a very limited life span (two hours). Gargantua seems mostly vegetal, and is able to use sound-based attacks (howls) as well as direct physical ones (taking apart the arena and using its pieces as weapons). Gargantua has enough physical force to overwhelm the arena's containment field and throw platforms through the arena's walls and right into space (along with Toji).
Gargantua ultimately self-destructs after Homme Du Feu witnesses Olympe being shot by Pissaro.
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