Heroes of the Storm has really been stepping up Blizzard’s tradition of pop culture references – largely originating from World of Warcraft. With a new line of character skins revealed there’s even more visual references to other intellectual property than in the past.
The most overt is the medic’s apothecary skin, both the visuals and name point to a clear Warhammer 40K inspiration (also the inspiration/origin of Starcraft’s canon.) But more often Blizzard is skirting potential legal conflicts by slipping in color variations clearly drawn from popular sources. The most recent of which are the medic’s Samus, and Artanis’ Evangelion palettes.
This isn’t coming out of nowhere though. Heroes of the Storm is chock full of pop culture references. Between the hero dances and in-game banter, it’s hard not to stumble into it. There are even occasional examples of this directly referential style, such as Sgt. Hammer’s Metal Slug inspired tank.
Still, it seems like Blizzard is fond of this approach. Heroes of the Storm’s last hero, Kharazim, had an entire third of his skins styled after references this way. Kharazim had 2 Avatar (animated series) inspired skins, and one referencing Dragonball Z.