Ever since the pandemic, the multiplayer gaming market has seen a surge in popularity, with many gamers using mediums like Steam to keep their online friendships burning bright. Multiplayer games allow players to work together to achieve a common goal; sharing and achieving wins with friends can make victory taste even sweeter. But not everyone can afford popular titles, and sometimes, indie darlings have more entertainment value.

Gaming on a budget? Look no further than these free-to-play co-op games on Steam; some of these rank among the best and most innovative the online gaming platform has to offer.

Updated on May 31, 2023 by Mark Sammut:Free co-op games on Steam are not necessarily in short supply, but most of them come with a PvP angle. If the selection is narrowed to only include PvE titles, the options suddenly become quite limited. That said, there are a couple of great titles on Valve's platform.

Co-op games that focus on PvP will largely be excluded.

9 Damnosaur

The world has been invaded by time-traveling dinosaurs in DAMNOSAUR. Players take on the role of the pink-haired heroine, Proh, in this colorful anime-style shoot-em-up. Equipped with various weapons in her arsenal, Proh must survive for as long as she can against the endless waves of these prehistoric fiends and save Jollywood.

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The longer she lasts, the more dangerous the dinos become, from terrifying Tricepatops' to the towering T-rex - one touch from these dinos and Proh is dead. DAMNOSAUR alsofeatures local split-screen co-op, so players can run-n-gun together through the chaos.

8 With You

With You is a wholesome cooperative puzzle-platformer game for just two players to enjoy. Together, the oddly-shaped couple must collaborate to solve a series of physics and platforming segments through problem-solving, gentle communication, and jumping on each other.

Short and sweet, with its intentionally-wonky controls, With You resolves to improve the bonds and intimacy between the two players and (quite literally) bring them closer together.

7 No More Room In Hell

No More Room In Hell is a first-person horror game where players can join forces with up to eight others and try to survive the zombie apocalypse with over 30 weapons at their disposal. There is proximity-based voice communication, so the further players are from one another, the harder it is for them to communicate.

Taking inspiration from contemporary sources like The Walking Dead, No More Room In Hell is surprisingly fun and guaranteed hours of entertainment. With the zombie virus running rampant, players can become infected and decide to warn their team of impending zombification or stay quiet about their fate.

6 Unsolved Case

Unsolved Case casts players as detectives and puts them on a serial killer case. In order to catch the Cryptic Killer, the two sleuths will need to solve a series of puzzles, and teamwork is the name of the game. Players will need to constantly communicate since each party is shown just a fragment of a room's overall puzzle, and a solution can only be found by combining each person's clues.

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Lasting approximately an hour, Unsolved Case is an enjoyable brain-teaser. While the free co-op game does not have much replay value, it is designed to act as a sample of what Eleven Puzzles' future Cryptic Killer games will contain.

5 Warframe

Celebrating its 10-year anniversary in March 2023, Warframe has expanded a great deal over its lifespan, a process that saw an exciting but limited third-person shooter grow into one of the most ambitious and best free-to-play games on the market. Despite hitting a few speedbumps along the way since not every change or update was for the better, Digital Extremes deserves praise for what it has achieved over the last decade.

Warframe can be treated as a single-player experience for the most part, and this sort of extends to the multiplayer component as well. Most missions can be taken on as part of a squad, and many people tend to just do their own thing rather than coordinate as a unit. Once someone is of a high enough level, they will steamroll through most encounters, to the point there is not much incentive to engage in teamwork. As such, it is very easy to get through these operations without having to interact with other people.

Even though the above is common when teaming up with strangers, Warframe is still supportive of multiplayer and online co-op. Four friends can have an absolute blast playing through most of the game's content together, an endeavor that should keep them busy for a couple of months. Co-op also makes grinding more manageable compared to solo runs.

Warframe has PvP modes, but the game still deserves a mention since its PvE co-op is far more extensive.

4 Bombergrounds: Reborn

Looking for a chaotic and fast-paced game perfect for parties? Look no further than Bombergrounds: Reborn, a colorful and modern battle-royale interpretation of the classic bomber games seen on retro consoles like the PlayStation One.

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Players have the choice of 15 different animals to control, each with unique perks and abilities, guaranteed to cause plenty of mischief and mayhem. While the main Battle Royale mode pits every player against each other, the game also has a few team-focused options that deliver chaotic co-op action.

3 Dungeon Defenders 2

When the Old Ones' armies of monsters attack Etheria, the kingdom calls upon heroes to resist the invasion. Across an array of maps, these brave warriors must defend their towers against the evil hordes, a process that evolves engaging in satisfying action RPG gameplay. Dungeon Defenders 2 is a fun tower defense game that prioritizes real-time combat, although there is still an element of strategy.

In single-player, users can create a party of four heroes that can be swapped at a moment's notice. In co-op, different players assume the roles of these heroes. Initially, only a few characters are available, but more can be unlocked through gameplay. Although not one of the most active games on Steam, Dungeon Defenders 2 still tends to average a few hundred players at a time, which is impressive for a smaller-scale title that has been out for nearly 6 years.

2 Alien Swarm: Reactive Drop

Alien Swarm might just be Valve's most forgotten game, although the 2010 release is by no means bad. In fact, anyone seeking a twin-stick co-op shooter can certainly do worse than this title; however, they should consider jumping into Alien Swarm: Reactive Drop instead of the original game. For one, Reactive Drop is still being updated despite coming out in 2017, which cannot be said for Alien Swarm. Secondly and more importantly, the expansion does exactly what it advertises: improve the base experience.

While not lacking a PvP, Reactive Drop is primarily about co-op. 8 players can take on one of the game's 10+ campaigns, each consisting of a couple of missions. Naturally, the gameplay loop boils down to players going up against wave after wave of enemies while they try to work toward a level's endpoint. Straightforward as this core concept is, Alien Swarm: Reactive Drop manages to incorporate quite a bit of nuance through its classes and tactics-driven gameplay. This is not one of those forgiving games that allow players to effectively disregard the rest of the team as they live out their Rambo fantasy; no, teamwork is necessary for survival.

1 We Were Here

Following the same thread as innovative puzzle co-op games like Keep Talking And Nobody Explodes, We Were Here sees two players lost in a frozen wasteland and separated. The only form of communication they have is through their handheld radio devices.

Both players must have working microphones to communicate as they work together through challenging puzzles to reunite. Both players will have an entirely unique gameplay experience. We Were Here is inspired by real-life escape rooms and has three other games in the series if players fancy more thrilling challenges.

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