Once upon a time, between the original Team Fortress and Team Fortress 2, there were a lot of team-based shooters--each with their own quirks. Enemy Territory has always been free and has always been huge fun. It's running on the Quake 3 engine, and if you're familiar, then you know what you're in for. The bunny hopping, gibbing, and arena gameplay are all there, but with a really well-done coat of WWII paint: Axis vs Allies. Each team has classes (just like Team Fortress) but instead of capture the flag, each map has different objectives which normally consist of capturing specific strategic points or blowing up targets. The maps take a while to learn, but even total noobs can have a ton of fun due to the simple gameplay and controls. The entire install is tiny, and servers can install mods which will load on the fly. This is a game you can play with friends (or your entire office, school, etc.) in minutes. This was actually the pick for my highschool LAN parties back in the day, and it was always a blast.
Much like Pony Island, Inscryption is a game which breaks the fourth wall and shatters your expectations. Go into it blind, and enjoy it at face value. If the pace changes, keep playing and your efforts will be rewarded. Production value is insane on this one, and everything is extremely clever. I never found the difficulty to be unfair or unenjoyable--assuming you play your cards right.
