The so-called Hel's Traps can be randomly discovered while exploring rock and forest locations. Luckily for you, some poor fellow has already fallen into a trap earlier. All that remains of him is a magical container, the Hel's Sphere - inside which you can find weapons and equipment.

It is impossible to get the sphere imperceptibly. When you decide to pull it out, the Call of Hel will turn on, which will call the dead to protect the trap. Eliminate all the guards and you can take the loot.