Steam free2play games that are not pay2win ?

War of the Roses, unless you want to play in a clan.

Realm of the mad god.

Alien Swarm, Dota 2

Bloodline Champions. Alas at the moment the situation there isn't exactly the best.

Any of those?

Forge.

Super Monday Night Combat

non-pay-to-win f2p game? that's an oxymoron.

Dota 2

APB RELOADED - I win a lot of matchs only with ingame weapons, you dont need to be premium player or the armas marketplace weps to win and enjoy the game, but highly recommended to be in a guild or with friends in TS/Skype.

Marvel Heroes.

I'm just waiting for Dirty Bomb. Splash Damage made an awesome game with Wolfenstein Enemy Territory. Brink not so much but I got my hopes up.

Warframe, best F2P

DC Universe

War Thunder is pretty fair being a F2P with a premium system. I mean you can go and buy a powerful plane, but once it's taken down that match they can't use it anymore.

Planetside 2 and War Thunder.

If you can stand moba community - Dota2 is by far the most fair F2P game out there.

America's Army and Alien Swarm, though they are much free games then F2P since they haven't a store or something like that...

Dota 2 is a sure bet. Realm of the Mad God was a F2P game with only cosmetic stuff, but recently this changed and it seems more P2W actually.

By P2W I mean games where you can pay to gain a good advantage on players that don't pay.

I'm not sure if someone already said but Super Crate Box and Spiral Knights and (not sure if completely F2P but it's really fun anyway) Fallen Earth.

War Thunder and Dota 2 are the ones I really recommend, I don't know about TF2 since I had it before it became f2p thus I have always been a "premium player"

The game that's the most p2w of all time has to be Battlefield heroes, oh god the greed... THE GREED!

valve f2p games, d2 and tf2

ROTMG, other is shit for kids.

TF2, Alien Swarm

Dota 2

DOTA 2