Magnet Pull as Much as Possible

With Magneto's Magnet Pull action, he effectively has a hand size of 6 in hero form. The draw back to this is that you churn through your deck and receive additional encounter cards fairly quickly. Regardless, I was using this ability every turn, especially once Magneto's Armor and Magneto's Cape were in play.

With Mutant Education, you can selectively return your identity specific cards, all of which are magnetic, to your deck. This dramatically slows the rate at which you empty your deck and see those additional encounter cards. A thicker deck also helps with this- this was intentional. Combine this with Erik's Survivor ability from alter-ego, Asteroid-M, and X-Men Instruction to control exactly what cards are in your deck as it becomes thinner and thinner. Selectively returning Wrapped in Metal and Magnetic Missile allows for the combo of these two cards to occur fairly predictably too!

Magneto's Magnet Pull action greatly benefits from Digging Deep and White Fox.

Protection was chosen so Magneto can control his health and selectively go to alter-ego when three desirable cards are on top of the discard pile.

Specialized Training was included, as the ready Magneto has access to every turn with Magneto's Cape allows him to benefit greatly from boosted stats, as well as increase his effective hand size even further.

With Armor, Polaris, "Come Get Me, Bub!", and Metal Shards, there is a ton of access to tough status cards, often meaning that the two basic activations you have each turn are almost always used to control the board- defeating minions and clearing threat. Magnetic Bubble is great at keeping Magneto alive as well.

This deck can be further improved- possibly by including Lockjaw to play from your discard on turns where you have too many of your 8 resource cards in your hand? I'm not convinced What Doesn't Kill Me is the desired protection card. Ever Vigiliant could potentially be better, as Magneto's Cape provides the Aerial trait.