Otherkin-Related Games
EXTREME alpha draft. Please note I have not played any of these games myself and this list is based on others' recommendations.
Elfae Spectrum | Other Types | General Mythic/Magic | Miscellaneous

Dragons
Draconia. (still in development 2021) "Draconia is an open-world dragon survival game with RPG elements being made in Unreal Engine 4. Play as one of six different dragon species and take over the sky or the land. Follow the path of Taruk and uncover the story behind Draconia through quests, secret locations and various characters in singleplayer and multiplayer mode."
Dragon Documentary. (2015) "Dragon Documentary is a very cool high flying action game that sees you controlling a huge dragon, burning towns, castles and armies with your fiery breath." Unfortunately this never progressed beyond a pre-alpha, proof-of-concept type state as of mid-2015. (recommended by itsadragonaesthetic)
Dragon: The Game. (2014) "Experience dragons in their proper role as the monstrous, complex, and epic protagonists that they are. In this open world action role-playing game you will bring your dragon's story to life. As you eat, age and hunt your dragon will develop allowing you to improve and customize its wings, tail, claws, and breath weapon." Also an incomplete early access version that doesn't seem to have progressed any further; they did a Kickstarter in 2019 but their actual website is now just a blank (so who knows where $35,000 went...). (recommended by itsadragonaesthetic)
The I of the Dragon. (2004, Steam / GOG) "The world of Nimoa is as beautiful as the morning dew, but only at first glance. Under the surface of hills and fertile valleys lurks an old and eternal evil. Living as a mould, stretching threads through an infected area like deadly toadstools. The center of this "being?" deep in the under world is the giant daemon, Skarborr. You, the player, take the role of the young, inexperienced dragon. In the role of the savior of Nimoa you move through the skies and faces all the challenges of the evil Skarborr." (recommended by itsadragonaesthetic)
Other Types
The following are more obviously suitable for therians, but may also appeal to nature spirits or others whose kinfolk is particularly connected to a natural environment.
The Endless Forest. (2006, with updates; 2016 on Steam; currently in redevelopment as of late 2020) "The Endless Forest is a multiplayer online game and social screensaver, a virtual place where you can play with your friends. When your computer goes to sleep you appear as a deer in this magical place. There are no goals to achieve or rules to follow. Just run through the forest and see what happens." (recommended by itsadragonaesthetic)
Meadow. (2016) "Heaven is a place called Meadow! Vast, teeming with life and now a unique social experience. Might and Delight invites you to frolic freely in the lush fields of Meadow - a unique multiplayer sandbox. ... Band together with other animals, form uneasy allies or choose to explore alone." (recommended by itsadragonaesthetic)
Last updated 5/11/2021