Unreal Engine
Unreal Engine is an engine that was created by Epic Games in May of 1998. Since then, 5 majorly different versions of the engine have been released. It's supported by multiple platforms, and as such, is a commonly used engine.
Tools
There are a couple of tools that exist for ripping assets from Unreal Engine games.
UModel
UModel is a tool for ripping visual assets from just about every iteration of Unreal Engine from 1 to 4. The github repo for it can be found here.