If you're looking for something to play this weekend and don't want to spend any money, Amplitude Studios has made a trio of Endless games—Endless Space 2, Endless Legend, and Dungeon of the Endless—free for the weekend on Steam. The Endless Space Collection, which includes the original Endless Space and the Disharmony DLC, is also free, but you get to keep it.
The free weekend comes alongside the release of a couple of new expansions, Penumbra for Endless Space 2 and Symbiosis for Endless Legend. All three games are also on sale, if the freebies convince you to jump in with both feet: Endless Space 2 is $14/£12/€14, Endless Legend is $8/£6/€8, and Dungeon of the Endless is up for $3/£2/€3.
As an added bonus for Endless Space 2 players, Amplitude is teasing new in-game content that will unlock based on the number of systems explored. The first, a new minor faction known as the Basryxo has already been unlocked. Four more pieces remain.
The free-for-keeps Endless Space Collection has to be claimed through Amplitude's Games2gether platform. It can be a little bit of a struggle but once you're set up and you Steam account is linked, you'll find the redemption button on the account rewards screen. Hit that, then check your Steam library, and like magic—there it is.