If you have a PC Game Pass or Ultimate subscription, you can install and play the full version of Diablo IV at no extra cost.

Blizzard occasionally offers "Free Trial" weekends or limited-level demos on Battle.net. 4. Diablo II and Diablo III (Paid Games)

You can download it directly via the official Diablo Immortal site or the Battle.net launcher. 2. Original Diablo (Free Browser Version)

You may find legacy versions (the 2000 original Diablo II or Diablo III demos) hosted on community archives like Internet Archive , though these often require a valid license key or CD key to fully install and play legally. Diablo Immortal

The classic 1996 title that started it all can be played for free through your web browser via reconstructed source code.

While is a paid game, there are ways to access it without an individual purchase:

and Diablo III are generally paid titles .