|“Now you must use it to create the Fusion Dragon. Only a Fusion Dragon can punch the depths of the Boiling Sea, and only the Dragon Blade can create one.”|
“You will make the impossible possible, and unify the Elemental powers of Fire and Water: the Fusion Dragon.”
|— Ray and Maya|
Symbolizing the unity of Fire and Water, the two-headed Elemental Dragon of Fusion is the only creature powerful enough to withstand the fierce environment of the Boiling Sea. It can be summoned only by the Dragon Dagger and is so strong-willed and powerful that it must be ridden by the Elemental Masters of Fire and Water – only when both Masters mount it can it be controlled. Ray and Maya were the first to ride the Fusion Dragon, using it to plunge to the depths of the Boiling Sea to hide the Reversal Blade, and later Kai and Nya followed in their parents’ footsteps to retrieve that Time Blade to save Master Wu.
- The Hydro-Electric Dragon is portrayed mainly as an Elemental Dragon of Lightning, so the Fusion Dragon is the first "true" Fusion Dragon.
- This is the third fusion dragon created, the first being the Ultra Dragon's metamorphosis, and the second being the Hydro-Electric Dragon from the combination of the Elemental Water Dragon and the Elemental Lightning Dragon.
- The Fusion Blade is needed to create the dragon because unlike water and electricity, water and fire do not combine naturally.
- Main article: Fusion Dragon/Gallery