I'm deleting the entry for Left 4 Dead because the Survivors are neither an invasion force nor an army (and they could hardly be called seemingly unstoppable)

I'm saying this because Edit Reasons sometimes won't show up for me

This troper has long considered the tunnels in the Second Death Star to be a deliberate attempt to provoke this, since they weren't there on the original Death star, and thus would serve no real purpose. Palpantine was a Genre-Savvy sod.