Ghosts are similar to Invaders and gives rewards in form of random stuff but also with rune fragments.

There are 6 levels of ghosts and to be able to attack them with your Shaman you must unlock them in the Shamans Knowledge. Attacking the ghosts gives your Shaman more experience.

Different ghosts appear during a limited time and give different rune fragments as rewards.

These are the types so far (with the type of rune fragments given):