StarCraft II’s Heart of the Swarm beta is underway.

The multiplayer-only test is initially limited to a select group of pro-gamers, members of the press, contest winners, and shoutcasters, but will open up to the general public soon.

Those wishing to participate in the beta can opt in by clicking on the "Beta Profile Settings" under the Account Management section of their account, or by signing in here.

Blizzard has said that signing up from a account that’s actively playing StarCraft II will help a player’s chances of being selected.

Further details on the Heart of the Swarm beta are available on the StarCraft II Community Site.

A release date for the expansion is yet to be announced.