Starcraft 2 Heart of the Swarm's new units
New Terran Unit: Widow Mine
The Widow Mine replaces the cut Shredder. Like that unit, it's a small, autonomous spidery thing, designed to allow Terran players to hold down sections of the map. But unlike that unit, it doesn't seem to have the potential to be game-breakingly unfair. Widow Mines have to burrow before use; once in the ground, they'll hop up and attach themselves to the legs/body/horrible gelatinous eye of anything that passes over them, before kicking off a short timer. Once the timer reaches zero, they burst, doing mad amounts of damage (currently 200) to their target. I tried building an army of fifty of them and scuttling into my foe's base. It didn't go so well - they don't target buildings, and he'd built a few Photon Cannons at the front to detect cloaked or burrowed units.