There is something special about PVE games that are mindlessly fun. Being able to just shut off your brain for an hour as you just enjoy the experience is quite rare among games nowadays.
Starship Troopers: Extermination
Starship Troopers: Extermination is an Early Access game recently released by Offworld Industries. It is a massive 16-player co-op FPS that puts the player on the front lines of a massive battle against the Arachnids. For those of you who have watched the films, read the books, or watched the CGI series this wargame does an excellent job of simulating their chaotic battlefields. For those who do not know this series, be warned. You will immediately be thrown onto the front lines in a hopeless struggle against aliens (bugs). You will try to gather resources, destroy hives, and even build bases all for it to come crashing down by the sheer horde of enemies. No matter how many objectives you accomplish, your only hope will be to safely extract. But do not expect to make it out safely with everyone on your team. This is the Arachnid's home world and they won't give it up without a fight.
I do have to point out one disclaimer. This game is a little janky at times with some of the worst performance I have seen, but it makes up for it by just being a lot of fun.