Anyone read Uncanny Avengers? They had Exitar the Exterminator arrive and he just... stomped the Earth. Literally, he put down his cosmic boot and wiped the planet off it. All of Earth's heroes combined could not stop him. Then, through time travel, the heroes repeated the situation again and did the same thing but could only slow the foot down just a bit. It took the likes of Thor, Death Seed empowered Sentry and Rogue with all the planets heroes to only slow the boot down.
So, Celestials... giving 'boot on an anthill' a whole new meaning.