Scarlet Witch - Money for Nothing and your Allies for Free.

Deck Concept: As the title implies this deck is built around the idea of building high cost allies for nothing or close to it. Summoning Spell, Chaos Magic, and Rapid Response do just that. Additionally, I am a Cheap Bastard so I had a LOT of fun playing 4 or 5 cost cards for 2 or less.

Turn 1 - you want to hard mill and use Superpowered Siblings and Spiritual Meditation to get as many as your upgrades out as possible. In particular, you are looking for The Sorcerer Supreme, Quincarrier, Helicarrier, Chaos Magic, Double Resources, Avengers Mansion, Scarlet Witch's Crest, and Agatha Harkness in that order. Mill everything else.

Allies - After you get out your resource generation cards and your upgrades just use your allies to the best of their abilities. Summoning Spell is there to get your high cost allies out and Rapid Response is there to keep them out after they die. When playing Summoning Spell make sure to count the allies in your discard pile to make sure there is one left in your deck for the spell to work on. (You have 5 of them total.) I also had a blast playing Nick Fury 4 turns in a row because of multiple Rapid Response and admittedly a lot of luck.

The Wanda cards should still be your priority however, so you will rarely pay the full cost of the allies. I did really like how this deck still has good targets for Chaos Magic even after you have built some of your upgrades. When paying for your cards out of your hand your first priority is still Molecular Decay, Rapid Response (if you don't have any out), and Hex Bolt.

Design Decisions

I originally did this deck as a Voltron style deck with a bunch of ally upgrades like Inspired, Power Gloves, Laser Blaster, and Reinforced Suit for placing on Yondu and Giant-Man. That deck does work but it can be punished if the cards come out in the wrong order. It has a higher "ceiling" than this deck but a lower "floor". By dropping those cards it also allowed me to include Inspiring Presence and United We Stand which will help keep those high cost allies out longer so they can do more damage.

I also looked at including Captain America but his best feature (starting with tough) is ruined by Rapid Response doing 1 damage when you bring the ally back.