Microsoft hasn't been very quick in its efforts of bringing Activision Blizzard's huge library to Game Pass, but now it seems that three new games are in the pipeline. Pure Xbox notes that the Microsoft Store pages for Call of Duty: World at War, Call of Duty: Infinite Warfare, and Tony Hawk's Pro Skater 1 + 2 now have banners labelled "included with Game Pass".
None of them have been confirmed yet, but mid-month Microsoft usually announces what we can expect from the second half, and it's undeniably mid-April right now. A reasonable guess is that these titles and more will be presented for Game Pass next week.