Serious Sam: Siberian Mayhem is a standalone expansion for Serious Sam 4, released in 2020. Croteam is responsible for developing the title. However, the publishing was handled by Devolver Digital.

Serious Sam 4 is the next full-fledged installment in the series of extremely bloody and dynamic first-person shooters, whose first two installments - both remastered nearly a decade later to HD - debuted on the market in 2001-2002. The Croatian studio Croteam is responsible for creating the title, as well as all the leading installments of the

PC game Serious Sam Classics: Revolution is the combination of the ‘The First Encounter’ and ‘The Second Encounter’ installments. Except for unifying both the games, Revolution has some additional features to further enhance the visuals and deepen the plot.