We still have a long way to wait for the eventual Diablo 4, and while we did get a decent playing game to hold us over with Diablo Immortal, the heavy monetization aspects were far from what fans wanted from a Diablo experience. The next true sequel after Diablo 3 has always been Diablo 4, obviously, though delays have pushed the game further and further into the future.
While we still don't know when Diablo 4 will release, that hasn't stopped fans from uncovering an unadvertised option to pre-register for the game's beta. For whatever reason, Blizzard hasn't officially announced this feature yet, but there's never any harm in jumping in early to hopefully secure your spot to play this upcoming action RPG as soon as possible. While it is simple to do, you will need to know how to pre-register for the Diablo 4 closed beta since there are no official instructions just yet.
Further reading
Blizzard details Diablo 4 customization options and new enemies
How to register for the Call of Duty: Modern Warfare II beta
How to register for Diablo 4 beta tests
Pre-registering for upcoming Diablo 4 beta tests is a quick and painless process. Here's how you can get it done in no time:
Step 1: Head over to this pre-registration page on Diablo 4's official website.
Step 2: Select "Pre-register" and sign in with your Battle.net account. If you don't have one, you can create one for free right there as well.
Step 3: Choose which platform you want to play the beta on, should you be selected to participate.
Step 4: Wait for an invitation and instructions on how to access the beta!
When is the Diablo 4 beta?
The reason Blizzard made a formal announcement about this pre-registration is likely due to the fact that we don't know when any Diablo 4 betas will happen. However, the fact that the option is up and functional heavily implies that they will at least announce beta periods soon, if not launch them shortly after as well.