9 Theories That Answer HUGE MCU Mysteries
3. Thanos Gave Loki The Mind Stone As A Plan B
Between Thanos' first appearance in Avengers Assemble to his infinity stone hunt in Infinity War, the only glimpses of Thanos we had were in post credits scenes and a tiny cameo in Guardians of the Galaxy. After Age of Ultron we see the Mad Titan collect the infinity gauntlet, vowing to do it himself.
This seemingly refers to Thanos taking matters into his own hands after being failed by Loki and Ronan in retrieving the stones for him. But why did he make this decision after Age of Ultron? There is no reason to believe he was behind the maniacal android's actions, so what exactly was it about Ultron's demise that prompted Thanos to gather the stones himself?
This theory states that while he sent Loki to conquer Earth as his plan A, plan B was the sceptre itself. Foreseeing his minion's failure, Thanos planted some sort of intelligence within the mind stone housed by the weapon, hoping this would manifest itself through a third party, Ultron, and continue the work Loki failed to complete.
However, Vision ultimately took over from Ultron as the owner of the stone, solidly placing himself on the side of the Avengers. This is when Thanos realised his plan B has failed, and decided to do it himself. It was the stone itself that failed Thanos, not Ultron.