I have gotten a couple of fellow DC gamers to join me in a fast paced FPS (first person shooter) known as Sauerbraten. It is similar to the old-school Doom type games, where you are always moving rapidly, and stuff can change in an instant. It is very fun and offers countless hours of insane killing 
Pros:
Many gametypes
Easy to learn
Not too "gorey"
Can become very funny at times
Runs on OLD hardware
Lots of nice effects for NEW hardware
Built in co-op map editor function (!!!)
POWERFUL map editor
AVAILABLE FOR WINDOWS, MAC, OR LINUX!
Cons:
Large download + patch (~216MB)
People in co-op editing can be a pain (online people)
(A few) Cheaters online
Bonus:
I can host games behind my router with no problem ON-DEMAND
I can host games behind my router with no problem for DEDICATED SERVERS
Myself, Deozaan, and p3lb0x have been making maps and battling each other for the past week, and the game can become really addicting. Unfortunately, I am planning on making all servers private/closed down to public due to my having to take 20+ minutes every time I get ready to save the DonationCoder map to clean up crap people leave and make it look good again (and not like a sandbox). But, more fun for us, right?
Here are some screenshots of the DonationCoder.com/wtfCody.com map - contributed to by those stated above, as well as several loyal players online that happened to join in and assist (or destroy
).
Sauerbraten official website: http://www.sauerbraten.org/
Come join us!
-Brandon
EDIT: File size correction

Pros:
Many gametypes
Easy to learn
Not too "gorey"
Can become very funny at times
Runs on OLD hardware
Lots of nice effects for NEW hardware
Built in co-op map editor function (!!!)
POWERFUL map editor
AVAILABLE FOR WINDOWS, MAC, OR LINUX!
Cons:
Large download + patch (~216MB)
People in co-op editing can be a pain (online people)
(A few) Cheaters online
Bonus:
I can host games behind my router with no problem ON-DEMAND
I can host games behind my router with no problem for DEDICATED SERVERS
Myself, Deozaan, and p3lb0x have been making maps and battling each other for the past week, and the game can become really addicting. Unfortunately, I am planning on making all servers private/closed down to public due to my having to take 20+ minutes every time I get ready to save the DonationCoder map to clean up crap people leave and make it look good again (and not like a sandbox). But, more fun for us, right?
Here are some screenshots of the DonationCoder.com/wtfCody.com map - contributed to by those stated above, as well as several loyal players online that happened to join in and assist (or destroy
).Sauerbraten official website: http://www.sauerbraten.org/
Come join us!

-Brandon
EDIT: File size correction
















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