Activision and Blizzard have said they will form "the world's most profitable games business" in a deal worth $18.8bn (£9.15bn).
US-based Activision also makes hit console games such as the Tony Hawk series and Guitar Hero.
Nine million people pay a monthly subscription to play World of Warcraft.
Vivendi will be the largest single shareholder in the merged company. With the new company's expanded resources, can we talk about Diablo 3?