Map for trolling using Warp Portal

[janamigs]

Hi all ! Is there a certain map where I can use /memo and warp my friend to that place? I just want to troll him. 

Like he gets to that warp and goes to an unknown map where he can't use any skill and has to walk out of that place?

[OrcLordDaddy]

Amatsu Dungeon, kill all the Hydras and then use /memo right in the middle of it.

[Playtester]

I once had someone send me to Thor Volcano Camp. Since I had never seen this place before (Thor Volcano is too hard for casual gamer to ever manage to get there) I was pretty confused and teleporting on that map was blocked so I couldn't just teleport back to my last save either.

I would assume this depends on server settings, though.