Source: Magnimar, City of Monuments, pg(s). 43-44
The Breakbag goblin tribe resides in the Mushfens south of the Varisian city of Magnimar, and is known for its love of broken glass. Industrious members of the tribe have even tried to make melee weapons out of it (with little success), but have incorporated shards of glass into arrowheads, stuck them into wooden clubs, and created makeshift caltrops out of glass and clay. The Breakbags love the sound that broken glass makes so much, that they carry around bags of it.
The Breakbags are the largest goblin tribe in the vicinity of Magnimar and are led by Chief Chuffskin. They hate the goblin tribes of Magnimar's sewers and believe themselves far superior, launching frequent raids against their urban cousins. These raids are generally the only way that Magnimarian citizens would come into contact with these goblins. The Breakbags are nomadic and maintain no permanent village, a practice that has made them quite difficult to eradicate.