Drix
This is the deck I've been using for the past season both climbing and at infinite rank and it got me a lot of 8 cubes winning due to the nature of the deck.
The idea is to have strong early game cards that can assure you are gonna win the early game and maintain priority. We are looking to play Magik on Turn 5 and then use Scarlet Witch/Rhino to switch from limbo to surprise our opponent. Many games when opponent sees Limbo they will play some weak cards or could even entirely skip turn 6 (because of she-hulk in hand) preparing for a big final turn. But surprise! The final turn just happened and you missed it
Zero has high power for a 1 cost and can be played before Titania/Lizard/Sword Master/Maximus. We are looking to play cards like sword master and Maximus (if they are not zero'd) on the last turn. Scarlet Witch/Rhino are used to switch limbo. If you have both in hand you can use one on locations that are restrictive. Sentinel provides good stats and keeps giving you cards to play. Cloak/Lizard are great stats for the cost and Cloak can make for some fun mindgames. Jessica Jones has great stats and we are looking to play her and then play Magik on a different location to ensure she will be a 4/8.
If I have one of SW/Rhino and Magik in hand by turn 5 I always Snap! I've got a bunch of people snapping back after I play Magik and then just emoting "I don't believe you" when Rhino comes down next turn and I steal 8 cubes. The idea of the deck is that you might have a 1-3 games where you retreat for 1 cube due to bad RNG but can swing it back fast with a 4/8 cube games which happen very often with this deck! So be smart with retreat/snaps and you will climb!