Heracross is a bipedal, coleopteran insectoid Pokémon covered in a blue exoskeleton. There is a long, pronged horn on its forehead. The horn ends in a cross on males and a heart-shape on females. On either side of the horn is a short antenna with a spherical tip. Heracross has oval, yellow eyes. Its forearms have a pair of spikes near the wrists, while its thighs have a single spike each. It has two claws on its hands, and a single long claw on each foot. There is a single pair of wings covered by elytra, which can be seen during its release from a Poké Ball in the 3D games. Heracross's claws allow it to dig into the ground for sturdy footing and also allow it to climb trees. Using its horn, it throws opponents or competitors for food. It can lift and throw objects 100 times its own weight. It uses its two antennae to search for food by scent. It lives in boreal, temperate, and tropical forests, where it feeds on tree sap.
As seen in the anime, Heracross has been known to compete with Pokémon such as Pinsir for food. The same episode also shows Heracross allowing Butterfree to feed on tree sap after Heracross has finished its meal. In addition, it is shown to suck sap from Grass-type Pokémon such as Bulbasaur. In Alola, Heracross get along better with Pinsir, as they both have rivalries with Vikavolt.
Forms
Heracross can Mega Evolve into Mega Heracross.
Mega Heracross is bulkier than its previous form. Thin orange markings now rim its head, hands, and shoulders. Additionally, there is a half-circle, orange marking over its eyes. It now has a long, pointed nose that curves slightly upward. Its back now lacks wings and is completely yellow. The horn on its head has grown into a large, simple spike with two smaller spikes on the front. The antennae have lengthened as well and now have ovoid tips. Mega Heracross's forearms have thickened and lost their spines.
This Pokémon has a high body temperature, so it opens the shells of its arms and torso to allow heat to escape. Mega Heracross boasts such incredible strength that it can lift objects up to 500 times its own weight between its horns. However, it is left with muscular soreness after reverting to its original form.
(Source: Bulbapedia)