|Title||Supreme Thunder Bug|
|Prior forms||MegaKabuterimon (Blue)|
|Cards||(Ja:) St-697, St-889|
Nature Spirits Digimon]]
AncientBeetlemon is an Ancient Insect Digimon whose name and design are derived from "Ancient" and "Beetle". It possesses the attribute of "Thunder", and is one of the legendary "Ten Legendary Warriors" that saved the ancient Digital World. Its appearance is fused from many insects such as the Rhinoceros beetle and Stag beetle. Its shell has a hardness rivaling that of Chrome Digizoid, so the falx on both of its arms can cut through anything, and it can easily lift up objects hundreds of times its own weight. Its abilities were later passed on to the "Insect Digimon".
Digimon Battle Spirit 2
D-Tector 2.0 and 3.0
- Calamity Thunder: Attacks with a calamitous thunder which brings about super-disasters.
- Tera Blaster: Attacks with a super-electrical discharge with a thousand times the power of "Mega Electro Shocker".