Seasons are free content patches for Warhammer 40,000: Inquisitor - Martyr, each released in 2-3 months apart from each other. 

Aside from providing new content (such as new terrains, enemy factions, etc.), they advance the plot of the persistent world in the Caligari Sector with global events.

The first test Season is set to be released during Steam Early Access, the first proper Season will be introduced after the release of the full game.