If a PC tries to put on a Cloaker while they think it's a cloak, how does it resolve?

Question

I've been thinking of putting a Cloaker in a campaign I am making and I want to use its trait False Appearance to hide. False Appearance is for the Cloaker is defined as:

While the Cloaker remains motionless without its underside exposed, it is indistinguishable from a dark leather cloak.

I'm thinking if a PC sees the Cloaker hiding, one may try to put it on; in which case I'm not sure how exactly to handle it. Would the PC get a perception check to realize it's actually a creature and if the PC fails, would the Cloaker remain hidden on the PC's back while the PC is moving?

Answer 1

The PCs would detect the Cloaker for what it is immediately as it is picked up. Presumably, only the topside of the Cloaker is camouflaged, while on the underside are its head, evil eyes and teeth. Here's the relevant text from the Cloaker's False Appearance trait:

While the cloaker remains motionless without its underside exposed, it is indistinguishable from a dark leather cloak.

Picking up the cloak would immediately expose at least some of its underside, revealing the Cloaker's more bite-y under parts. At that point, the Cloaker has achieved its goal as an ambush predator, it's gotten close enough to its prey and is going to surprise the poor PC.

If, somehow, the Cloaker weren't discovered and the PC puts it on, it's best to really think about the creature's motivations:

• Is it a minion of another stronger NPC?
• How hungry is it?
• Does he think he can take the PCs all at once, or is he going to wait til the guy who put him on is alone?

I recommend reading this TheAngryGM article (TRIGGER WARNING: swearing and jokingly belittling players) about encounters, setting up conflicts and creature motivations as further reading.

Answer 2

The exact wording of that trait reads:

While the Cloaker remains motionless without its underside exposed, it is indistinguishable from a dark leather cloak.

So if the Cloaker is motionless, there is no check to be done. It cannot be distinguished from a dark leather cloak. But as soon as it is in motion, it is no longer indistinguishable.

Note that "not indistinguishable" just means that -- it can be distinguished. It isn't necessarily revealed at that instant that it becomes distinguishable. At that point, it is up to you, the DM, to decide how the PCs find out they're wearing a living creature.

You could use the rules on Hiding to accomplish this. Have the Cloaker roll a Stealth check when it's moved. If the check beats out the PCs' passive Perception, it stays hidden. Otherwise, the Cloaker is detected.

Alternatively, you could do a Deception vs Insight contest... though using Insight on a cloak is a little strange.