Both "Serious Sam" games debuted on Windows and utilized Croteam's in-house Serious Engine.

Entity and relation annotations:
id: 0
type: entity
value: text: "Serious Sam"
labels: <Production>
id: 1
type: entity
value: text: Windows
labels: <Production>
id: 2
type: entity
value: text: Croteam's in-house Serious Engine
labels: <Production>