Agnaktor is in many ways similar to Lagiacrus; both are quadrupedal Leviathans of similar size and body shape. It is noted for its remarkable ability to swim through lava and tunnel through solid volcanic rock. Its body is covered in a lava-like armour which hardens when cooled and softens when heated. It has a drill-like beak which is lined with rows of needle-like teeth.
Its fighting style is similar to that of other Leviathans. It can charge at a hunter, "swim" straight through solid rock in order to smash into them and produce a powerful orange beam, highly reminiscent of the one produced by Gravios. Its skin is coated in lava armor that is usually orange-red, indicating that it is heated and vulnerable, but if it goes too long without using its fire beam or being physically exposed to heat, the armor will cool, and become black and hard. In areas with physical ceilings, it may tunnel through the roof as well as the ground.
Agnaktor are quite aggressive, challenging all others that encroach on its habitat, due to the fact that it has no natural predators at an adult age. The only threat that it encounters is if a monster challenges it for territory or food.
Agnaktor is found exclusively in the Volcanoes of the New World and Volcanic Hollow of the Old World. It is highly adapted to life there, and is at home amongst the lava pits and rocky slopes. It does not stray from magma- and lava-filled areas.
Also known as fire-pike wyverns, Agnaktor use their tough beaks and great strength to burrow through rock, and sometimes even cave ceilings. Encrusted with hardened lava that can soften from the heat when they spit magma or burrow.
Also known as fire-pike wyverns, Agnaktor use their tough beaks and great strength to burrow through rock. However, their hardened-lava armor becomes soft when they burrow underground or are attacked with fire or explosives.
When low on stamina, Agnaktor will fail to produce its Heat Beam.
It will either sleep or prey on a Rhenoplos in order to regain stamina.
Sonic Bombs will trap Agnaktor, much like Monoblos and Diablos. Tossing a Sonic Bomb instantly after it has successfully burrowed into the ground will trap it. Also, like the Monoblos and Diablos, it is immune to this effect during Rage Mode.
When a certain part of the Agnaktor is wounded, and the lava broken off, that part will not cause weapons to bounce as much, even if the Agnaktor's other body parts have hardened.
If a Flash Bomb is thrown in Agnaktor's face during its 360 fire beam, it will become stunned and will crawl out of the ground.
Agnaktor, and its subspecies, have the largest amount of body parts that can be broken. These include their beaks, chests, fins, four legs (each one can be broken individually), and their tails (Broken, not severed). This adds up to eight total body parts broken, not including a severed tail.
Hitting Agnaktor with a fire-elemental weapon or projectile will make its hardened armor soften up.
Any form of explosive damage (from Barrel Bombs to Gunlance shells/Wyvern's Fire) will heat up Agnaktor's hardened parts, making them soft again.
Agnaktor receives no damage from the Dragon element when armoured, but it becomes its main weakness when its armour has been destroyed.
High Rank Agnaktor gains a sweeping heat beam while on land, but Agnaktor only sweeps it to right, making its left flank a relatively safe area.
While Agnaktor is underground and a large monster roars, it will affect the Agnaktor the same as a Sonic Bomb.
Agnaktor also has a new attack where it will do a singular break thrust into the ground.
At G rank Agnaktor gains a new move in which it will do a singular thrust into the ground and then do two more singular thrusts while moving slowly to the right or left.