Overwatch

Overwatch is a multiplayer first-player shooter created by Blizzard Entertainment. First unveiled during BlizzCon 2014, it entered closed beta for North America and Europe on October 27, 2015. It was released on May 24, 2016. The preorder of the game was announced and made available for prepurchase on Battle.net on November 6, 2015.

Hearthstone references

 * The house in the bottom right corner of the Gadgetzan battlefield feature references to the Overwatch characters Genji and Hanzo in the form of a green-edged katana, shurikens, and arrows, the weapons of those two heroes. The sword, when rapidly clicked/tapped on, has a green dragon that spins around in, in a confirmed reference to Genji's Ultimate ability, Dragonblade. The distinctive "Pachimari" doll fished up from the docks is also originally from Overwatch.
 * Four Hearthstone cards can be found lying on a table on the Overwatch map Castillo.