Is it Illegal to Use Assets from Another Game for Research Purposes?

EULA stuff isn’t necessarily legally binding, like how they’ve added stuff about how you can’t sue if stuff doesn’t work properly (that’s not going to hold up in court) but for reverse engineering stuff it would be up to the judge to decide, and they’d probably go with the software developer.

Copyright on the other hand, is pretty clear, they made the content and didn’t give the rights for people to use it outside of the game.