In recent times, Call of Duty has undergone a shift towards featuring more crossover characters from different franchises. Examples of this trend include characters from The Boys and Lara Croft from Tomb Raider.
Recently, Call of Duty has revealed the details of its Season 06 content update with a ghostly theme, coinciding with the Halloween season in October. One notable addition to the game is the playable character Spawn. However, what has created even more buzz is the inclusion of characters from the Blizzard universe, under the same parent company. Inarius and Lilith from the game Diablo have been brought into the Call of Duty world.
Previously, we hardly witnessed any collaborative activities between Activision and Blizzard (except for the use of Battle.net together). The reasons behind this were difficult to ascertain, but now, the sharing of universes between the two sides is beginning to happen in reality.
Season 06 also introduces several other characters, such as Alucard from Hellsing, Ash Williams from Evil Dead, Skeletor from Masters of the Universe, and even weapons from the game Doom, which are set to arrive in the near future.
TLDR: Call of Duty’s Season 06 update brings a ghostly theme and introduces crossover characters from various universes, including The Boys and Lara Croft. Notably, characters from the Blizzard universe, specifically Inarius and Lilith from Diablo, make their appearance. This collaboration between Activision and Blizzard is a new development, and additional characters from different franchises are also joining the game.