The top sellers have returned for a single day encore of Steam’s Perils of Summer Sale and several Unreal Engine games are among the list:

Borderlands ($10.19) + all DLC 66% off ($3.39 each)
Killing Floor ($5.00) 75% off
Thief: Deadly Shadows ($2.99) 85% off
BioShock 2 ($14.99) 50% off
Mass Effect ($23.99) 40% off

There are several other non-Unreal Engine […]