If you haven't heard of it, AssaultCube is a really good, lightweight game that functions as a basic FPS and is quite easy to start out in cheating with, but also has the ability to cheat in more advanced functions like aimbot once game hacking comes easier, and there are hundreds of tutorials on getting started with cheat engine in AssaultCube. (Note that while there is Online mode, stick to singleplayer since it's just easier)
A lot of these types of (low graphical) games don't require you to download 2gb+ which is neat.
I've played all of them and they seem fun enough to pass time.
I am only getting back into these games since I am back on a low end laptop..
Have a try, see what you think.
Depends if you want to "get them legally" or not
For the games that are free + DRM Free you can try out
Teeworlds (obv not the steam one - however you can probably just download from steam and take the files out)
Armagetron Advanced (Retrocycles on steam - same case as above)
Pretty sure AssaultCube has LAN (not sure though - https://assault.cubers.net/)
Hey, I don't remember the tricks you described (maybe I was just bad lol) but every other trait made me think of Assault Cube
EDIT : if not, then maybe check Urban Terror. I remember this one having rocket jump tricks and being fairly popular in the 2000s
I really don't want to believe it, but this exact thing has happened to literally every other Early Access shooter I have ever invested in, ESPECIALLY survival games.
Developers: Gameplay first. Gameplay first. Gameplay first. It doesn't matter how many cool guns and maps you have if the gameplay is not good. It. doesn't. matter. at. all. I've played AMAZING games where you have almost no variety. I can't stress how utterly important it is to make sure each and every player has AGENCY. IF that is being taken away for any reason, there's no longer any point in playing, because your decisions don't matter.
Netcode/Desync, UI bugs, hackers, and bad storytelling and game design can all infect and destroy a game from the inside.
Assault Cube. It's just a basic FPS, but it can be so much fun with just a few simple mechanics. You can choose 1 of 5 different primary weapons to spawn with (an assault rifle, a sniper rifle, a Carbine, a sub machinegun, and a shotgun), alongside a pistol and a knife, for a variety of game modes like Team Death Match and Capture the Flag. There's also a number of movement tricks, too; You can crouch jump to jump a little higher, you can move diagonally for extra speed, you can even use the kickback of the Assault Rifle to jump higher or farther, or you can do a grenade jump (although the grenade jumps are never worth it). This can really open up potential for parkour on a number of maps. On top of that, the game is very small and runs well even on old computers and even over a slow internet connection.
1) https://assault.cubers.net/docs/commandline.html Try to set "--mastertype=0", maybe it will help. Otherwise see if you can ping or do other general connection tests to assault.cubers.net:28760. Maybe you can't resolve the domain but you can reach the IP and configure that as the masterserver using the -m flag. Next try the forum at forum.cubers.net as this place will be slow to respond.
2) Not as much as before. Still enough to give you a good taste of it. I say you've missed the golden age.
3) Xonotic and Warsow are nice but I think they're relatively dead now too. Try looking into shooters for Linux because these will generally be cross-platform and low-resource.