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[Game Giveaway] Dark Sector, made by Digital Extremes before Warframe, is free to acquire until the 30th
(store.steampowered.com)
This game has a few technical issues. Widescreen is broken by default and the maximum horizontal resolution is limited:
https://www.pcgamingwiki.com/wiki/Dark_Sector
There are also stability issues, especially on modern hardware. It's not a particularly great game anyway, not even by the standards of AA games from the 360 era. I would only recommend it to die-hard fans of Warframe who want to see some early versions of assets and designs they are used to. IIRC, some assets are even identical. At least it's very short.