What's a game that's like Killing Floor

Hm... Orcs Must Die is close, only with less weapons and more traps.

The MP is a little different as well.

Dungeon Defenders is also more along the lines of traps.

I doubt you'll be able to find a wave FPS exactly like Killing Floor.

I don't know if I am the only one,but Payday:The Heist feels similar.

iirc binary domain multi is comparable? to killing floor. i can't attest personally since i've never played either.

Mass Effect 3's multiplayer...kinda.

It's wave-based, but you do all your weapon shopping and equipping outside of the match.

L4D :O

if you are looking for a 4 co-op game then either payday the heist, left 4 dead would doo, if you are looking for survival by rounds then maybe orcs must die

Dead island Bloodbath arena delivers similar waves of enemies but no buying, you bring your own weapons first

Crossfire could be but its not steam

man vs machine in tf2

sniper elite nazi zombies

Mann vs Machine mode in Team Fortress 2 has wave defence, upgradable weapons, and is a first person co-op shooter

Gears of War 3 horde mode has waves fun and gets challeging hopefully you dont just play pc of you do than sorry

Nation Red, not FPS though

Sanctum

Defense Alliance 2 mod/ mw3 spec ops survival mode/ sr3 whored mode

Sanctum

Tetris

Left 4 Dead 2

Can't think of any other games that haven't yet been mentioned. Pretty much any wave based games... Don't think there are zombie games exactly like that, L4D is similar, but the waves are spontaneous, depending on where you go to, not the time scale.

brainbread

bulletstorm multiplayer,wave of enemies,buy and upgrade weapons.

Zombie mode in Black Ops 2.