I'll fire off a few Free To Plays: -Dirty Bomb: [spoiler]A character-based multiplayer shooter where one team leads an assault on a location while another team tries to stop them. Currently in beta, but also just released a new character, map, and special event.[/spoiler] -Spiral Knights: [spoiler]This may be a bit grindy for your tastes, but I'll recommend it anyways. This game is a sort-of MMO in which you try to fight your way through somewhat procedural dungeon and levels in an attempt to reach the core of a planet.[/spoiler] -Survarium: [spoiler]Think of this game as a PvP version of STALKER.[/spoiler] -Blacklight Retribution: [spoiler]A cyberpunk shooter where you play as either a mercenary or a member of Blacklight, a special forces unit made up of other special forces members. Armed with the latest tech, you take on different tasks (mostly in the form of pvp game types) throughout the world. Known mostly for it's HRV (basically in-game wallhack, and the closest thing you have to a minimap) and the fact that the weapons are very customizable.[/spoiler] -Ghost in the Shell: First Assault: [spoiler]Nexon's taken their access of the GitS license and given a dev team a chance to make a character-based multiplayer shooter out of it. Apparently it's going to get a revamp on the 18th.[/spoiler] -Trackmania Nation Forever [spoiler]Some years back (maybe 10, don't remember), Trackmania Nations came out. This is a revamped version of that game, and the last Trackmania game to follow the old business model of the series (one free version, one deluxe version with a price tag). The series itself is known as an easy to learn, but difficult to master racing series which focuses on your attempt to beat the best time of a track. It could be the default tracks, or it could be a track designed by other players. Also, you can make your own tracks.[/spoiler] Mechwarrior Online: [spoiler]Another installment in the Battletech Universe, this one taking place in the war between the Clans of the outer rim of the galaxy, and the people of the inner core of the galaxy. In it, you play as one of many mech pilots fighting for a side. There are a variety of mechs you can choose (but not my favorite, the Mad Cat Mk2) and customize, and the tutorial does a decent job in teaching you how to be a pilot.[/spoiler] HAWKEN: [spoiler]If you think Mechwarrior Online would be too slow or too complicated for you, then there's aways HAWKEN. This is a faster-paced mech combat game set in a world that's slowly being eaten by nanomachines.[/spoiler] Alien Swarm: Reactive Drop: [spoiler]Remember that free game Valve made from that game mod called Alien Swarm? Well, some people went and made a better version of it with more options and Steam Workshop support, and it got greenlit. So, if you want a top-down shooter where you and up to 7 other people fight through a horde of alien bugs, this game's for you![/spoiler] War Thunder: [spoiler]A game about WW2 vehicle combat. You can control planes and/or tanks from different nations in the war and take part in battles both realistic and unrealistic.[/spoiler] Tyrian 2000 [spoiler]An older sidescrolling shooter in which you play as a betrayed member of a former company, out to stop their attempt at galactic domination. It, and a few other games, are free on GOG.com[/spoiler] Join the Raiders of the Broken Planet closed beta: [spoiler]Can't guarantee you getting in, but it's worth a shot. This game is a third person cooperative shooter in which you run a mission against one of three human factions. There's also an option to play as an antagonist, a lone doppelgänger of one of the raiders working to stop the raiders from completing their mission, with the help of whatever AI enemies normally spawn in this mission.[/spoiler]

Go to humble bundle and for like $10 you'll get like 8 games

Stardew Valley.

Another free game is, Dr Langstove, the tiger and the terribly cursed emerald. I'm paraphrasing because I don't remember and with a name that long it makes sense. It's pretty short, maybe an hour max to find everything and interact with everything, but it is very good and funny. It felt kinda like Portal if Portal went't about puzzles or portals.

Unturned is fun with friends.

Loadout is an awesome Third person shooter with gun customization and the MICROTRANSACTIONS ARE PURELY COSMETIC

Team Fortress 2 used to be a lot of fun, haven't played in a while but I imagine it's still going strong