...IDK if I like this new Jean (Live Dangerously)

The goal is to play Live Dangerously and then use Shadowcat to cancel it the bad effects.

From there, you want to keep recurring Shadowcat and play her every turn so everyone at the table gets two extra cards each turn. The main things that can slow this down are not drawing into X-Men Instruction and being unable to kill Shadowcat before your next turn, like when the villain schemes. In multiplayer, this is easier since you can just have her chump block for someone else.

To recur Shadowcat from the discard, you need Cerebro in play and X-Men Instruction in hand. There are three copies of X-Men Instruction, along with Mulligan, to help find the pieces of this combo. Once Live Dangerously is in play, if you draw an X-Men Instruction you dont need yet always carry it over to the next turn, unless you know for a fact that you will be able to recur Kitty the following turn.

Storm is an ally you want to keep healed with Tic-Tac-Toe. She lets you move threat around between schemes depending on which one is the biggest problem. Not My Responsibility is also useful here since it can erase the two threat moved while killing Shadowcat at the same time. If Storm didnt fit into my cost curve, starting with Cyclops also provides you a lot of future resource tempo. Remember you can always shuffle another ally in addition to Shadowcat from the discard to your deck.

Once the engine is set up, you can just dump threat onto Live Dangerously using Storm's ability since it's still a net benefit for the table as long as you silence it often.

Mulligan can be squeezed for extra value. Put cards under Plot Convenience, or use them as resources for Tic-Tac-Toe or Stick-To-Itiveness before playing Mulligan to draw back up to max Hand size so you effectively get some resource advantage out of it. Also if you have Mulligan in hand, try to use cards during the villain phase since the limitation on playing Mulligan is no cards played that phase.

Laser Swords should generally be saved for the endgame under Plot Convenience. You can share it with a teammate who has readying potential, or wait to put it on yourself once you've Unleashed.

Phoenix's hero cards are also pretty bad before you Unleash, so they're good Mulligan targets early on.

When you find Pool Inspection while Live Dangerously is out, its generally worth it to use it. With power counters, +2-3 resources from one of the Pool Resources, or a card under Plot Conveneince you can play it while still having enough left over for a Shadowcat recursion play. 7-8 Hand size is OP. Ideally try and keep a Pool resource, or Pool Inspection under plot convenience for this purpose during the mid to late game.

Specialized Training is the second priority. The sooner it is knocked out the better, but mostly it's there to give teammates something to thwart while they are blocked by the Crisis icon during their turn, which will happen if they go before you can replay Shadowcat for that phase and they either don't like to request hero actions or are using basic activations.

Save Live Dangerouslyfor later in the first deck cycle or in the second cycle. You'll want Cerebro at the bare minimum and your other core supports and upgrades (Plot Convenience, Healing Factor, Stick-To-Itiveness) either in play or attached to Plot Convenience and be relatively healthy before playing Live Dangerously because afterwards you will be focused on Mulliganing for Shadowcat Recursion and Pool Inspection almost exclusively. You can deck cycle really fast with Mulligan, and store Live Dangerously for the right time with Plot Convenience.

EDIT: After doing a few more games of testing. I dont think you need TicTacToe since X-Mansion was enough healing for self and allie. The extra resource was competing for more readies or extra allies. I also didn't need Cutupper. I think Colossus would be a good replacement for it as an ally that can block twice. In games where I got Healing Factor and White Hot Room the constant heals made landing the triple resource kicker on the Pool Resources made set up a breeze. But in missions with heavy hits at the start lost me some tempo, at least in solo. Consider putting in Colossus since you can often pay for him in your starting turns with one Triple resource or a double and your Phoenix Force charges.