WMG / Avengers: No Surrender

Candidates for the Big Bad:

• Thanos since his Black Order is involved
  • Jossed: The Big Bad is revealed to be The Grandmaster, and an unknown Challenger, who chose Earth as a battleground.
• Voyager
  • Jossed: The Big Bad is revealed to be The Grandmaster, and an unknown Challenger, who chose Earth as a battleground.
• Hank Pym/Ultron
  • Jossed: The Big Bad is revealed to be The Grandmaster, and an unknown Challenger, who chose Earth as a battleground.
    • It's also illogical for Ultron to be the Big Bad because he would not keep some Avengers in stasis, as his goal is to Kill All Humans.
    • And on top of that, Ultron is busy being the Big Bad of the concurrent cosmic event Infinity Countdown.

Voyager is another Elder of the Universe:

• They all have that sort of title.
  • Confirmed! She's Grandmaster's daughter.