In the advanced combat tutorial with Diego, if you defeat the puppet, leave, and come back into the arena before turning in the quest, the tutorial tries to start again, but the puppet is gone. Diego's message box also removes the UI for the options to teleport out. I'm not sure if the teleport hotkeys still work, but if they don't, the only way to get out is to open your friends list with its hotkey and teleport to a friend, which is what I did, since logging out and back in puts you in the arena and tries to start the tutorial again without the puppet. Even if all of the hotkeys still work, if a new wizard doesn't know those hotkeys, or knows the friend list one but doesn't have anyone on their friends list to teleport to, they're stuck there forever.