Gigamagnet

The Gigamagnet was a large military-grade hyperpolarized magnet which was used to win the Great META War. It was developed by Mister Nefarious and the science team at Black Mesa.

When finished, the magnet was roughly the size of a small personal pizza. However, the invention could extend out to over 5 million times its size, covering a large portion of North America. Mister Nefarious used this magnet to remove all Combine forces from North America (and later, the rest of the world). The Combine forces were all frozen to death in space and shot out into the cosmos at lightspeed. The Combine Death toll from this incident alone likely weighed in at roughly 10 million deceased. The Gigamagnet collided with Neptune's moon Triton, the location of the Combine's Polus Base, and sent the moon careening out into the cosmos.