dtgreene: By moving a potion out of the way and replacing it, at the last minute, with a gem, it is possible to consume it. In fact, it is possible to consume more gems than you have, causing a rift in the universe that gives you 65,535 gems, that can be sold to a merchant to get rich without disrupting the economy.
If you're clever and do things just right, you can prevent somebody from being captured, and can then take her with you while you go rescue her anyway, allowing you to take take two of her with you.
If you suddenly huge (with the help of a spell) when you are in a tight space, you can end up teleporting through a wall.
Wandering in circles over a magical trigger point while somebody else keeps doing the same action repeatedly can cause the universe to think that lots of stuff has happened.
It is possible for you to find a girl who collapsed while you attacked her, have her rest, and then have the attack happen. In this case, there will be two of the girl, one attacking you, and one with you.
Drawing a picture during a battle can produce strange results, including causing the entire universe to collapse.
Trickery can cause the dungeon to collapse, with you in it.
If you go fast enough, even walls will not stop you; you will just go right through them as if they weren't there.
Supposedly, there exists something called "save corruption", but nobody knows what it is.
It is possible to trick the universe into playing pong.
Ok... at this point you're beginning to miss the point of the thread. It was about general stuff in medieval/fantasy settings that are common in RPGs, not pointing out specific bugs from a single game.
