Thundermon

Thundermon is a Mutant Digimon similar to Mamemon. His Japanese name is Thunderballmon. He is also known as the "Digimon Dynamo". Thundermon can move faster than any other Digimon. 10 million volts of electricity surge through his body.

Digimon Adventure 02
Cody and Digmon encountered a Thundermon in the sewers underneath a village of Punimon. It attacked Cody and Digmon and one of its attacks reverted Digmon back to Armadillomon. When Thundermon caused the sewers to collapse, Armadillomon digivolved to Ankylomon and Thundermon could not penetrate him. He was however too fast for Ankylomon and was able to throw Cody up into the air. However the DigiDestined was saved by a mysterious Insect Digimon which then destroyed Thundermon after a short battle. It then turned out that the Insect Digimon was in fact Stingmon, the digivolved form of Wormmon. During the battle against Golemon, it was realized by T.K. that Thundermon was made from a Control Spire by Arukenimon. Later on, two Thundermon were seen during the final battle against MaloMyotismon.

Digimon World 3
Seen in the Dum Dum Factory.

Digimon World Dawn and Dusk
Thundermon (known as Thunderballmon in the games) digivolves from Kokuwamon, and can digivolve to Mamemon.

Attacks Variations / Subspecies
 * Thunder Volt: Fires a bolt of electricity.
 * Thunder Bomber: Throws electric bombs at enemies.
 * Intercepting Bomb (Intercept Bomb)
 * Thundermon X