How people extract (rip) assets from games?

Hello folks,

I’ve been watching few videos, of scenes rebuilded in Unreal Engine 4 from older games, but my question is how the people get their hands on the assets?

Popular example is Bioshock

or Unity

How that works? Someone knows?

It’s illegal to rip assets from most games

Im not so sure that its illegal, what it IS illegal is to then use them somewhere, i think just ripping them is not illegal.
Most UDK games were hilariously easy to decompile, there was a program somewhere that extracted the art files AND decompiled the unrealscript code for UDK and UE3 games.

Yea, there was and i tt was, but still, in most licenses you agree when installing (which no one reads) usually contain that you can’t do any type of backwards engineering, extracting, modifying etc.