Three characters from Blizzard's retro co-op game The Lost Vikings are now playable in the company's multiplayer online battle arena release Heroes of the Storm, according to a new blog post.

The three Lost Vikings, Olaf, Baelog and Erik, work as a single unit and are categorized as being very difficult to play. Each of the characters can move, attack and be killed separately, and also feature an individual respawn timer when they are killed. They can also be controlled together and have special abilities that can only be triggered when working as a single group.

Blizzard president and co-founder Mike Morhaime first announced plans to bring these characters to the game last year. The Lost Vikings was originally released in 1992 for SNES, and later came to DOS, Amiga, Sega Genesis and Game Boy Advance.

Check out the new heroes in action below: