Can anyone explain me how this interacts? Deathwacht allows you to identify creatures as undeads (among other things), and the haunts are, according to the Gamemastery Guide; “The distinction between a trap and an undead creature blurs when you introduce a haunt”
So I have no idea but I’m supposed to do when I’m the DM and this interacts. Should I allow a Perception check with a -4, similar to the effects of the spell detect undead, or what?
Rules within haunt say:
Although haunts function like traps, they are difficult to detect since they cannot be easily observed until the round in which they manifest. Detect undead or detect alignment spells of the appropriate type allow an observer a chance to notice a haunt even before it manifests (allowing that character the appropriate check to notice the haunt, but at a –4 penalty).
So at best, it might work like detect undead. However! This raises a good point I had forgotten about.
In a thread lurking somewhere on this forum is a discussion about Deathwatch and how it functions. In the discussion it was decided that it does not reveal information about things you are not aware of, because otherwise it steps on the toes of See Invisibility, Detct Undead, etc by using a very low level spell which has a relatively long duration. It was decided that it should not funciton in that way, and basically means you must be aware of the creature before Deathwatch will give you information about them. It will not ping and tell you a creature is there like the Detect line of spells. That is why those other spells exist.
So, no they shouldn't get to Detect the haunt exists with Deathwatch. Once they start to experience things from the haunt using Deathwatch could reveal that it has an undead connection, and may enable them to know it is a haunt with an appropriate Know(Religion) check.
If instead they used Detect Undead they might know about the haunt before they set foot in the area or set it off.