I’ve created a teleporter system in Blueprint. The teleporters are portal style, where if you enter one you get instantly transported to the target teleporter. Is it possible to modify nav meshes so that my AI can use teleporters to reach areas not otherwise accessible?
It is!
The magic keyword is “Nav Link Proxy”. They can be used to specify where the AI can leave the navmesh and where it will go.
Usually used to jump down somewhere it can also be really useful if you have doors, teleporters and similar stuff 
Edit: To be entirely honest I only know for sure that it works with doors. Not quite sure about teleporter.
That’s precisely what I was looking for, thanks!
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I know this is an old post but did you ever get this to work? I have been running into issues as the nav links don’t work over large distances, only to the next nav mesh tile.