Two-player stealth games
One game, and its whole idea is that neither role is assigned. Guard and Thief keeps the coins you can spend in the other player’s vault, so the moment you leave your own floor you are the thief and they are the guard — and you still have to come home to bank what you carried. About a minute, and a good part of it goes on deciding whether to set off at all.
1 game, played by two people on one device.
Stealth games
A round takes about 1 minute.