They then have to submit proof of their donation, which will then be added to a running total.
Once 666 quarts (1332 pints) of blood have been donated in total, the sweepstake will open.
At that point, any US player (whether they’ve donated blood or not) will be able to enter the competition via Instagram and Twitter (details on how to enter will follow when the target is reached).
The grand prize will be “a custom liquid cooled PC infused with real human blood”, according to Blizzard.
The PC will include an NVIDIA GeForce RTX 4090, an Intel Core i9-13900K, 64 GB of DDR5 RAM and 3 TB Gen5 NVMe M.2 SSD storage, and will come in a custom Diablo red/black colour palette with Season of Blood graphics.
Although the PC can only be won by US residents, the campaign will also unlock in-game items, which will seemingly be available to all players worldwide.
Once tier one (33%, or 439.56 pints of blood) has been reached, players will get a Bloodpetal Anlace dagger, a Bloodpetal Sever axe, a Bloodpetal Blade sword, a Bloodpetal Bludgeon druid staff and a Bloodpetal Heart necromancer offhand weapon.
When tier two (66%, or 879.12 pints of blood) has been reached, players will also get the Loch Raeth Maor armour for the Barbarian class.
Finally, if tier three (100% or 1332 pints of blood) is reached, as well as the sweepstake unlocking players will also get a Vermillion Eye Piebald mount.
At the time of writing, the campaign has already reached 27% progress, meaning around 360 pints of blood have already been donated in the name of Diablo.