There seem to be some hidden portraits in Heroes of the Storm, for example the alpha portrait, or the level 40 beta portrait.
Does the level 40 alpha portrait also exist? What are all the hidden portraits and can you/how do you acquire them.
There are currently twelve hidden portraits in the game. Some of them you are no longer able to obtain:
Alpha Player
Awarded for playing during the technical alpha.
Alpha Hero
Awarded for reaching player level 40 during the technical alpha.
Beta Player
Awarded for playing during the beta.
Beta Hero
Awarded for reaching player level 40 during beta.
Lunar Festival
Awarded for playing 10 games during the Lunar Festival holiday.
BlizzCon 2014
Awarded for attending BlizzCon 2014 (or purchasing the virtual ticket).
Wonder Billie
Awarded for making a real money purchase during alpha or beta. (Also grants the Wonder Billie mount.)
Billie the Kid
Awarded for making a real money purchase after the game was released. (Also grants the Billie the Kid mount.)
Heroes of the Dorm
Awarded for submitting a fantasy bracket prediction for the Heroes of the Dorm tournament.
Launch Week
Awarded for logging in during the first week of release (June 2, 2015 - June 9, 2015).
Reward for the Heroes Facebook page receiving one million likes. Awarded for logging in between June 30, 2015 and the release of the next major patch.
Golden Tiger
Rewarded when redeeming the Golden Tiger mount key found in the Heroes of the Storm Starter Pack.
There is also a portrait from a TeSPA promotion. TeSPA Chen (Chen wearing a graduation hat with a TeSPA logo in the lower right corner).