Got those from a summer promotion:
Quote
Greetings, Hero!
Thank you for being part of the Heroes of the Storm Second anniversary celebration!
As a thank you for voting in the third week of our contest, we would like to give you this code to use on your battle.net account to redeem a Hero and a skin.
Tychus + Prisoner Tychus skinStitches and Bikini Stiches bundleThe Stitches skin is not available all year, only during summer.
Starting bid for Tychus bundle: 50 fg
Starting bid for Stitches bundle: 100 fg
I do not know how many skin color variations come with it, so just treat it as the base skin / tint only.