My base got overrun by by the black-suited lizardmen which quickly killed off my all my soldiers with plasma bazookas, but not my little tank. It ran out of ammo quickly however so I decided to park it in front of the command centre door expecting it to get exploded quickly. The aliens however has no such plans, and surrounded it, ran away from it or just meandered around the base. Earlier tanks faced quick deaths in the face of concentrated plasma fire, why won't they fire at this one?
After a while I started to get bored and drove my tank away from the command centre door, but still the aliens did not want to win; they kept running to and from the tank but didn't breach the command centre or attack the tank. I ended up just aborting the mission.