Call Me, Call Me Any, Anytime

Overview
This deck is focused on getting out Mantis as quickly as possible. Since release, I had been playing Drax exclusively in Protection so I could mitigate damage and hopefully get a Med Team down to keep Mantis around. This worked, but things were always difficult when I didn't see Mantis until late. So I started playing around with the combo of Call for Aid and Make the Call to speed things up. You lose the damage mitigation of Protection, but if you can get Mantis out quickly then you won't need it.

The Main Tactic
Call for Aid obviously doesn't put Mantis into your hand, but it will have done one of two things after you play it: put Mantis in your discard pile or bring her closer to the top of your deck. If it's the latter, then great, but if it's the former, that's where Make the Call comes in. The risk is discarding all of your copies of Make the Call along with Mantis, but that's just a risk you have to play around to the best of your ability (after War Machine releases, ally Black Panther will probably be included in this list to go get your Make the Call if this happens). As a stand-in for the healing from Med Team, I have included Reinforced Suit, Team Training, and Rapid Response. This doesn't get you the same level of healing that a single copy of Med Team does, but if you can get out two or three of those cards (and potentially use Make the Call on her) then you should get enough healing out of Mantis to close out the game.

The number of Avengers allies in the deck is an interesting lever to play around with. Fewer allies means that Call for Aid digs deeper and makes Mantis available sooner but runs the risk of losing your Make the Calls, while more allies lessens the risk of burning key cards but doesn't grant you much of a benefit in speed. Three feels about right for me, but your taste may be different.

The Rest
I chose 2-cost allies to keep the cost curve low (and I almost always play Ant-Man for 2-cost, but the option to go bigger is there) and kept them in Leadership for the sake of the Power Of's. Rapid Response, Reinforced Suit, and Team Training are here to keep Mantis around or bring her back along with Make the Call. Maria Hill requires no explanation. Strength In Numbers is here to assist in digging through your deck to get out key cards, and sometimes using allies to draw you a card rather than attack or thwart is the best option. You also rarely ever block with an ally due to Drax's ability. Finally, Booster Boots is probably the easiest slot to change, but it prevents a little bit of damage and slightly accelerates allies into your discard pile so it fits here. Not a critical piece though.

Mulligan
In your opening hand, assuming you don't have Mantis, keep Make The Call, Call for Aid, DWI Theet, maybe an Energy/Genius/Strength, and nothing else.