What are the best free games on steam?

Survarium, my #1 game in hours played (not a bit of donation needed to win). But you need to live close to a server (there are only 3 currently - CIS, EU, NA)

Also Fistful of Frags is allright if you like online shooters, though a little too cartoony this one.

Path of Exile (outside Steam too). Very good free online game (with cosmetic, fully optional microtransactions, no boosters whatsoever), you can play solo or in a group, nice story, gameplay variety, solid endgame. You should definitely try it if you like the genre.

Super Crate Box is my favorite.
Mostly because I keep forgetting there's good free games on Steam as well, and you can't keep them in library after uninstalling so I lose track of them too easily :/

Look interesting:

• Transmissions: Element 120 (a short single player experience set in the Half-Life Universe)
• The Desolate Hope ("It's kind of a JRPG/Platformer hybrid with metroidvania elements.")
• Path of Exile (well known Diabloesque game)
• Floating Point (a peaceful, free game about using a grappling hook to swing yourself gracefully through randomly generated spaces)

Card Hunter. Way better than Hearthstone.

Team Fortress 2

Nobody mentioned Alien Swarm yet? That's pure heresy.
http://store.steampowered.com/app/630/

Duelyst
A card game based on a grid board with wonderful pixel art
Excellent Game

Path of Exile

Clicker Heroes. Be careful, it's ADDICTING.

Single player: Mandagon
Multiplayer: Tribes: Ascend

Marvel Heroes 2016 - Part Diablo-style ARPG, part MMO, part Marvel Universe RPG, with one of the fairest free-to-play models I've seen. Yes, it will take a while to get every hero, but there are over 60 heroes at this point, so that's not surprising. They also have a lot of special events that allow free to play players to get premium items and currency for free. In addition, you can "test drive" each character up to level ten, which won't give you a perfect feel for them, but it does give a clearer idea than just a spreadsheet of abilities will. I tend to play it in bursts, either when there's a special event going on, or when I get a superhero/ARPG craving.

PlanetSide 2

moirai
just play it. it's like 10 minutes most, but I assure you haven't played something like it

Duelyst.

Do Free Editions of games count too?: Toxikk

Some short ones worth trying:

Princess Remedy in a World of Hurt
You Have to Win the Game

Planetside 2(my favorite FPS) and War Thunder(my favorite tanks and planes game). You don't need Steam to play them, but they're on the store.

depends on definition of "free"

a large portion of them will be free to pretty much try, but are heavily locked down until you pay for sub, or dlc, or something.. its all bout those micro-transactions now.

if we include that category then some can be pretty damn good, but rather expensive to continuously play. Example: DC Universe (a subscription is pretty much necessary though - so i do not really recommend / but cannot deny it is pretty well made other then its greed)

PATH OF EXILE

Team Fortress 2

Paragon
(Moba outside of Steam but very good - made by Epic Games)

Mortal Online.

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