From September 26 through October 10, StarCraft cosmetics for each of Diablo 4's six classes, as well as a Zerg mount and mini Hydralisk pet, will be available for purchase in the in-game shop. Blizzard has not yet revealed the price of these cosmetic bundles, but if they are anything like Diablo 4's previous Berserk crossover, expect to pay around $28 per bundle.
Players can also claim a legendary shotgun called the Forsaken Chaos by viewing two hours of the game via the Borderlands 4 category on Twitch. Gearbox notes on the Borderlands website that Midnight Defiance and Forsaken Chaos can't be earned at the same time, so collectively a person would need to watch four hours of the game to obtain both legendary weapons.
The three items available in the Shock N' Awesome Twitch Drop campaign include the Metal Menace Wrap, obtainable after 30 minutes of viewing, the Tome of Skulls after 60 minutes, and the Skeletal Cyberscythe after 90 minutes.