Ubisoft announces the Skull Rain update will come tomorrow to Tom Clancy's Rainbow Six Siege, their first-person shooter. They offer this trailer showing off the patch, and this page has all the details. They also explain how the content of the pack will or won't unlock, depending on whether you have the season pass:

The Tom Clancy’s Rainbow Six Siege Skull Rain update will be available on August 2 and include a new Favela map, the most destructible environment to date, and introduces two new BOPE operators: Caveira and Capitão. Caveira is a ruthless interrogator who uses her stealth technique, the Silent Step, to sneak up on her targets undetected. Capitão is armed with a tactical crossbow which can fire lethal asphyxiating bolts and micro grenades that allow for quick and unexpected attacks.

Starting August 2, the Favela map will be available for all players and Season Pass holders will instantly receive the new BOPE operators. Non-Season Pass owners can unlock the operators with Renown or R6 credits starting August 9.Tom Clancy’s Rainbow Six Siege is currently available worldwide for Xbox One, PlayStation®4 computer entertainment system and Windows PC.