- Jumping body press. Distance is about the 'Bug's entire length.
- Thrusts its needle-like appendage on its head. Very narrow and range differs with size.
Their attacks usually consist of a stinger thrust from their mouth and a body rush tackle. With a hard shell and high HP, these guys take a beating. Try hitting them with Poison or Plague to supplement your damage, also melee attack with magic enchanted weapons (like rune sword) works fine. (Note that there is also a holy mace in the level if you can't find any magic stone.)
There aren't too many of these. In the tunnels where you first encounter the giant kind, they (thankfully) won't have the room to do the jumping press attack, and there will be opportunities to let them get stuck in smaller tunnel openings, or to get behind them. If they find themselves unable to move forwards in these tunnels, they'll try to stick you with their stinger, slowly rotating left and right to aim it at you, and occasionally shuffling back and forth. Easy kill. Even easier if you're behind them: They'll simply keep attacking in front of them, and you can stand behind it and beat at it in peace.
If encountered outside, especially if there are two, they get riskier. Keep in mind that they can't get inside of the tunnels, though, allowing you to whittle away their health between attacks. Outside, they'll favor the jumping press, and it really hurts when a giant one's doing it.
The giant bearbug explodes when killed! Once you have reduced their HP to zero, they will begin to rumble. This gives you the oppurtunity to distance yourself safely. If you do not run, expect it to dish out anywhere from 300-1000 damage when it explodes.
If you have the spell Soulsucker, get near one and kill it instantly. Run far away, and raise your Fire Resistance shield.