Login ambushing is an interesting strategy; it encourages forethought on both ambusher and ambushee sides. I don't want it to be removed from the game.

However, having a central game mechanic that breaks immersion so totally seems awkward. What if a new stealth feature, burrowing, was added, with the intent of exactly matching the effects of logout/login, but without breaking immersion? The idea would be to allow players who want to ambush to do so without having to log out of the game.

Any bot, at any time, could burrow, and it would take one minute of standing still. Then they would lose the ability to see, but would be perfectly undetectable, until they unburrow.

We could reasonably allow players to chat and browse market while burrowed, which would provide a small but real incentive to use the burrowing feature (with its possibly better animations) rather than logging out.