Symbiote Supreme, Human Torch, Magneto, She Hulk, and Doctor Doom should be pretty good for getting to the Champion, with Symbiote Supreme, Doctor Doom, and She Hulk being great Champion counters. Sorcerer Supreme is another good option.
For your a first run at completion I definitely recommend Doom. His easy access to stagger and nullify are great, and the block proficiency is very handy once you hit the 10% stage.
Also recommend the Mystic Dispersion mastery if you use him
Comments
Unfortunately i think he won't be viable for the instant shrug off phase
But that 6* sym Supreme should be enough for the champion
Also recommend the Mystic Dispersion mastery if you use him