Why isn't Blizzard expanding its universe with crossover RTS games? It has such a wealth of unused/dead characters that can be featured in Secret Wars type events to revive its most fledgling franchises, namely Diablo and StarCraft. Can you imagine an unknown entity reviving The Burning Legion to invade Diablo in Diablo 4? Or Warcraft vs. StarCraft in an inter-dimensional, self-contained clashes of universes?
Diablo vs. Warcraft: Sanctuary of Ashes
Kil'jaeden mysteriously arrives in Sanctuary and unleashes a powerful magic that revives Diablo, forging an alliance that lays siege on the Angiris Council. Tyrael, the new Aspect of Wisdom, leads the charge to fight back as a Fel-empowered Diablo slays Tyrael, and declares a new war on heaven with Kil'jaeden's backing. It appears someone on the Pantheon has been corrupted, and is inter-dimensionally siphoning power directly from Sargeras to Kil'jaeden unbeknownst to Illidan, his jailor. A new Host of Angels must take up the fight against the union of Kil'jaeden and Diablo, communing with The Light to raise warriors of The Light from Azeroth to knew well Kil'jaeden's weaknesses--Uther the Lightbringer and Tirion Fordring. Angels and Paladins must battle side by side against this new diabolic council of universes for not only the fate of Sanctuary, but the entire multi-verse! However, one of Heaven's greatest angels has turned rogue, tipping the balance in favor of Diablo and Kil'jaeden, inciting civil war. Can Sanctuary possibly survive?
StarCraft vs. Warcraft
Would you be interested?