Lavagon

Lavagon, known as Magma Dragon (マグマドラゴン) in Japan, is a virus from the Mega Man Battle Network series. The virus appears in and out of hole panels, warping around those panels and breathing fire at its target. They always appear on stages which have a total of 3 holes.

Lavagon
Lavagon is a red dragon virus that breathe red fire, which results in a homming panel lock-on, where a fire pillar rises from the ground, dealing damage; after the fire pillar disappears, it leaves a fiery ring on that panel. They appear in the Apart Comp 3 from Kotobuki.

Bluegon
Bluegon, Blue Dragon (ブルードラゴン) in Japan, is a blue dragon virus that breathe blue fire which results in a homming panel lock-on, where a piece of ice projects from the ground, dealing damage and freeze the panel it hits. They appear in the last battle (#20) of the SS License test.

Yellowgon
Yellowgon, Yellow Dragon (イエロードラゴン) in Japan, is a yellow dragon virus that breathe yellow fire (electricity), which results in a homming panel lock-on, where lightning strikes from above, dealing the damage. They appear in the last battle (#30) of the SSS License test.

Battle Chip
Lava Dragon, known as Magma Dragon in Japan, is the Battle Chip obtained from Lavagon. It only works when used in front of a hole panel, making a Lavagon appear from the hole to attack all enemies ahead with a powerful fire breath.

Other media
In MegaMan NT Warrior, Yellowgon is one of the electric viruses that appears in episode 28. In episode 56, a Lavagon appeared from the first Dimensional Area and captures Ms. Mari, but is deleted by Lan and his friends before it can do any harm to her.

Trivia

 * Since the variants of Lavagon, Bluegon and Yellowgon, only appear once each and after the completion of the game's main story, some people are not aware of their existence (as evident from various spriting sources, who claim that the two viruses are not present in the game, while their sprites are part of the code).