Assassin (ToME)

The Assassin class is somewhat similar to a rogue, but whereas the rogues of ToME are better at employing magic, thieving items, and installing traps, the assassins are better at being stealthy and fighting with weapons.

Stealth means that monsters are less likely to notice assassins walking or running around in the dungeon. This is good, because it easier to fight a single monster without waking up a nearby group, and it is easier to flee from monsters without having the other monsters on that level wake up and pursue the assassin as well.