A treasure goblin is a small demon from the Diablo series of games that is known for stealing and hording glittering objects. In Diablo III, they appear for a short time before vanishing into a portal, and if players kill them before they are able to escape they are rewarded with a large amount of items.
In StarCraft II: Legacy of the Void a treasure goblin during the mission "Into the Void" on an island in the southeast corner of the map, surrounded by treasure. If attacked, it will vanish into an invisible portal, leaving its sack behind. After a second, it will then reach out of the portal and take its sack with it.