"Should such a Skaven, or ‘Sack Rat’ as the troops have dubbed the blasphemous thing, be cornered and killed, a resourceful citizen can lawfully procure the contents of the sack of loot, if said contents are used in the battle against the invading vermin hordes."
- —Sergeant Schenker, Ubersreik Garrison remnants, Emperor’s Rest Hotel, The Hill.[1]

A lowly Sack Rat.
Sack Rats are greedy and cowardly Skaven, tasked with ransacking towns and villages of their valuables after an attack.
Overview[]
All the races of the Old World have their distinct priorities and wants and needs. For the Skaven, both individually and as a faction, the lure of power is their sole drive and motivation. While the intricacies of Skaven psychology and society would require a lengthy essay or twelve, a basic knowledge of their verminous motivations will serve well enough for the layman or citizen desperately fighting for his home.[1]
Among Skaven, Warpstone is the most coveted resource and commonly used as currency. Slaves, weapons and armour are other necessary tools in the scheming and brutal scramble for power that is the Skaven existence.[1]
Unlike the Humans and Dwarfs, the Skaven masses see no inherent value in gold, and a lowly Clanrat would most probably ignore a coffer full of a treasure for some juicy meat, a rusty sword or the tiniest speck of warpstone.[1]
Shrewd Skaven leaders with ambition and vision, however, see the value of gold and valuables as the means to influence and corrupt the greedy man-things of the surface world.[1]
Among the Clawpacks of warrior vermin assaulting Ubersreik, there are reportedly Skaven agents carrying large sacks and seemingly acting independently from the invading force. They scour the town for valuables, most likely on orders from an enterprising chieftain or warlord, pouncing on the opportunity to expand their influence.[1]