An Xbox Game Pass subscription is not necessary to play. Call of Duty: Warzone 2.0 falls under the free-to-play standards.

Fortunately, Warzone (in every capacity) is totally free to play across PlayStation, Xbox, and PC platforms  it's also a crossplay title, which has served to unite cross-platform players.

IW Engine is a next-generation game engine employed in the highly successful series of Call of Duty. The engine is developed in C/C++ and Python language.

Call of Duty is a video game series and media franchise published by Activision, starting in 2003. The games were first developed by Infinity Ward, then by Treyarch and Sledgehammer Games.