Microsoft's Xbox Game Pass service is set to have a huge second half of September 2021, as the company is adding a whopping 13 games in total. Instead of releasing these new Xbox Game Pass games all at once, though, Microsoft likes to spread things out. It added Flynn: Son of Crimson to Xbox Game Pass on September 15, and now, on September 16, it's added another three games to the Xbox Game Pass lineup, including two day one titles.

First up is I Am Fish, a physics-based platformer where players control a variety of fish in different situations. I Am Fish is already generating some buzz thanks to its bizarre premise and sharp sense of humor. It doesn't have very many reviews just yet, but the ones that have been published are mostly positive. In any case, I Am Fish being a day one Xbox Game Pass game should certainly give it a boost, and it will be interesting to see how many subscribers check it out while it's available on the service.

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The second day one Xbox Game Pass game added on September 16 is Skatebird, a quirky indie title that's basically a Tony Hawk game where the player character is a bird. Skatebird reviews have been mixed, but fans of the skateboarding game genre may still want to look into the game nevertheless.

The third game added to Xbox Game Pass on September 16 is not a day one title, but rather it's a game that originally launched for Xbox in 2020. Superliminal is a puzzle game that earned somewhat mixed reviews as well, but it's also earned some award recognition. In any case, Xbox Game Pass lets subscribers try any game without paying a cent more, so those curious can play it with little risk.

These three games aren't the only titles on deck for Xbox Game Pass for the rest of September. The other new Xbox Game Pass games for September 2021 include stealth-action game Aragami 2, open world indie game Sable, turn-based FPS Lemnis Gate, and classic-style JRPG Astria Ascending. Needless to say, there's quite a bit of variety when it comes to the new Xbox Game Pass games for September 2021, so there should be something of interest for just about everyone.

Meanwhile, Game Pass subscribers already know some of the games they can look forward to playing in October as well. Phoenix Point is joining the Xbox Game Pass console lineup on October 1, while Back 4 Blood is coming on October 12.

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