Deadly mummies

I already half expect to be ambushed by a mummy when I enter a pyramid. I know better but still I carefully peek around every corner instinctively. This should be a thing, and not just a regular monster that can be easily defeated by a single player, but something a little more dangerous that requires more than one person, or some very resourceful tactics to survive. They should be inside random sarcophagi just so you don't know which it is in. Also, lootable and removable sarcophagi would be very cool.