I picked up ENSLAVED™: Odyssey to the West™ Premium Edition during a Humble Bundle sale. After checking https://www.protondb.com/ first of course. It runs GREAT in Proton!
I was using Proton 5.0-8 but I'm sure it runs fine in Proton 5.0-9 as well. Cutscenes, gameplay, performance, load/save all worked as expected. Definitely worth the sale!

150 years after a global war, a survival ship crashes in America. Play as Monkey (the beefy strong tempered tough guy) who is forced to escort Trip (the young beautiful woman) through city rubble, puzzles and mechanical enemies. Work together and traverse your way across dangerous terrain using parkour, weapons and Trips special abilities.