American Comics: I Crashed Into Ancient One and Became the Sorcerer Supreme?

Lin Du accidentally transmigrates to the American comic-book world and gains the ability to fuse with anything, acquiring special powers from whatever he merges with.

Before he can seek out the heroes of American comics and fuse with them to gain their abilities, he accidentally sends the Ancient One flying while she is fighting Kaecilius and his followers.

What kind of delivery just shows up on his doorstep like this?

Lin Du fuses with the Ancient One and gains energy projection, the ability to pass through objects, teleportation, interdimensional travel, and the power to summon things from a distance.

He fuses with Kaecilius and gains the abilities of Dark Blades and Dark Power.

He fuses with Dormammu and gains the energy of the Dark Dimension, granting him immortality, the power to warp reality and destroy galaxies, travel between dimensions, create pocket dimensions, manipulate the timeline, and control the multiverse!

Mordo: Is this what they call a genius? He became the Sorcerer Supreme in less than a year!

The Ancient One: I knew I was right about him. His abilities far surpass mine. He is the only one worthy of the title Sorcerer Supreme.