Space Station 13 is a community-developed, top-down, tile-based, mind-boggling, face-melting, limb-hacking video game running on a shitty freeware engine made in 1996. In a fashion not dissimilar to Dwarf Fortress, the game has been developed so much so that each mechanic is super-intricate and can interact in ways that will surprise you even after a thousand hours of gameplay. For example, one can build a cryogenic tube system filled with a chemical that makes a mouse burrow out of the occupant's orifices, resulting in one dead person and literal hundreds of mice.
Upon creating your character (or letting the game do it for you if you couldn't be arsed), you may pick from a number of jobs upon the space station in which the game takes place, ranging in responsibility from the actively detrimental Clown to the all-powerful Captain. The game is designed so that each job can be synergistic in some way with one another. For example, the Science department can provide useful upgrades to any member of the crew, or a player who wants to undertake a project such as building an unconventional power engine will probably want to source goods from Cargo and enlist the help of everybody in Engineering.
Therefore, player interaction is always encouraged and rewarded. One must be wary though, as bad actors such as traitors and cultists with sinister motives could be posing inconspicuously as one of your fellow colleagues, or hostile factions such as space ninjas and wizards run amok, hellbent on destroying the station.
It's a game that can have you laughing uncontrollably from the absurdity of your demise - like the time an explosion launched a loose wire at me, bisecting my skull and instantly killing me.
It's a game that can leave you rattled - like after a harrowing round where the crew tries their hardest to fight off an alien hivemind, then realizing it's a lost cause; leaving the survivors to arm the contingency nuke, and turn their gun on themselves.
Seriously, I have been so deeply immersed in the atmosphere of this game, and have felt every kind of strong emotion while playing as a result. Though I don't get to play much anymore due to a lack of free time, Space Station 13 is such a unique game that will forever be near and dear to my heart as no experience could ever match it.