Hi everybody, just purchased this great game but i am in doubt with the horror check. Let's say you did not defeat a monster in the combat encounter (but succeeded the horror check) and you want to fight it again in the next round. Does the investigator have to do another horror check or does he do the combat immediately?

All combat encounters start with a Will test (unless the monster does not require one to happen), so, yes, you have to check Will again

Ok thank you very much for your answer!

You're welcome

In the Role playing game frequent encounters, if not leading to madness, could inure an investigator to further exposures to mythos denizens

So for a Byakhee with a sanity loss of 1d6, would require 6 succesful checks on 6 seperate encounters leading to immunity from future checks.

It could be a useful way of showing a Soldiers detatchment from the dead, i.e no sanity checks for seeing dead people and halved for Zombies. A surgeons professional detatchment etc