Metaltech: EarthSiege is a mech-simulator game published by Dynamix in 1994. It takes place on Earth approximately 400 years in the future when the planet has been overrun by the Cybrids, a mechanical race created by humanity.
The player controls a giant vehicle called a HERC (short for Humaniform-Emulation Roboticized Combat Unit with Leg-Articulated Navigation) which is essentially a walking tank. HERC's are equipped with various weapons, shields, and other advanced gear. The game consists of over 30 missions which range from recon to strike missions against Cybrid bases. The ultimate goal is to drive the Cybrids off of Earth.