We're going to have a LAN party today and I'm looking for games that aren't dependent on Steam for multiplayer, so fire away! :)

I'm looking for co-op and tournaments mostly, there's going to be 2-6 of us, so recommend whatever you like.

Preferred genres - but anything is fine! are:

Platformers

FPS

Fighting games

Tabletop/card games

Space dogfighting games (esp. the ones we can jump in quite easily and don't have to spend 20 minutes in a tutorial!)

Roguelikes and 2D action/adventure games

Thank you! :)

It'd be so freaking awesome to have a GOG friends LAN party by the way, where all of us would just get together and smash those games like Unreal Tournament and Mario together!

No idea what a LAN party is, but the best multiplayer games I know of are:
Divekick
Anything from the Street Fighter or King of Fighter series
The Trine Series
I've heard Keep Talking and Nobody Explodes is good, but haven't played it.
Dunno if they rely on Steam or not.

Are you including physical board/card games? Because I've played some 50 or so and know just what to recommend depending on your situation/preferences.

Starcraft/Broodwar
Sacred Gold
Sacred 2
Torchlight 2
Doom
Duke Nukem 3D
NeverWinter Nights
Diablo 2 (Zy-el mod)

SNES?? (If the emulator supports Multiplayer via Netplay, then most multiplayer games will let you play, although most of them will be up to 2 players...?? Probably fighting, or racing games)

Halo 1&2 (Maybe?)
Quake (maybe?)


Hmmm....

Unreal Tournament 2004 is fantastic for LAN parties.

Oh. In that case, nevermind everything I said.

1nsane (available on GOG!)
Age of Empires II with the UserPatch
Blobby Volley
Call of Duty 1, 2 and 4
FlatOut 2
Starcraft
Unreal Tournament (2004 or the original)
Warcraft III

No no, only real videogames, I don't have many boardgames. :)

And to add to what rtcvb32S was saying, we're going to be either connected to the local LAN via internet or LAN cables.

Terraria's mutliplayer is tons of fun

Allow me to clarify:
I have no tech knowledge whatsoever and don't even know what LAN means.
Also, looky here:
http://www.giantbomb.com/profile/nikral/lists/top-lan-party-games/44789/
http://store.steampowered.com/curator/6859938-LAN-Party-Games/
https://www.reddit.com/r/Games/comments/1nwovn/the_best_and_most_accessible_games_for_home_lan

For FPS take Quake 3 Arena, Unreal Tournament (which one is up to personal taste) and Serious Sam.

If you also want to try Real Time Strategy install Starcraft, Warcraft 3, Battle for Middle Earth 1 and 2 and Battle Realms.

I don't really know many multiplayer platformers and those I do know usually play on one computer and not over the network. The only exception that comes to mind which also happens to fit the Roguelikes and 2D action/adventure description is Terraria which I can highly recommend.

RTS and FPS games tend to work the best since a lot of people can be in the same game at the same time.
Minecraft might also work, although that tends to be a bit of a long game.
If you don't mind splitting people up there are also co-op games you can throw in the mix like Portal 2.
And if there are enough people games like Battlefield could be fun.
Before Minecraft we'd also play games like and [url=http://www.openlierox.net/]Liero.
A Diablo-clone might also be interesting.

I'm iffy about this one. I mean it can be done, but latency and dropped packets become an issue, while playing local LAN you have the best speed and reaction times... you also start getting multiplayer issues where guys are glitching around due to slow ping, or the game can make weird calls as to what happened.

Right, usually the same room, but definitely the same building and close enough that you can taunt each other.

Pretty much anything from the '90s that supports IPX is a good bet. And pretty much anything most other games probably have a server available that you can set up. It wasn't until more recently that companies forced you to use their servers. Anything prior to Steam and popular is probably going to be worth looking at.

I personally think that simpler games like Doom, Warcraft 2 and the like are better for these sorts of things than more recent games anyways.

Counterstrike

EDIT: it seems you need steam to play even the original Counter-strike?