Pretty sure it’s on the devs for making the buggy games though. IIRC, ET is unbeatable without cheating or playing a patched version. It’s far from the only one with problems.
Dark Templar from StarCraft. Just going about your business then suddenly you’re sliced in half.
A Ghost dropping a nuke is pretty scary but not much different from the real life possibility of dying from a mile you didn’t know was coming. Just not from an invisible person.
Being infested by the zerg would be pretty terrifying too. Not really a specific unit though, I don’t think. Haven’t played in quite a while.