The Ronin

I always wanted to play Psylocke with Psy-Flail Strike, but I found it complex to use in order to get the most value out of it. Either Psylocke's defense wasn't high enough and you'd take damage without much way to ready afterward, or you'd play other defense events to maximize this aspect so as not to take damage and to activate Unflappable, which ultimately led to a cost that was way too high just to deal 3 damage and a stun. As soon as I saw the new protection cards, I immediately thought that Psi Flail Strike would now be much simpler to use. It's now very easy to raise your defense to 5 with Psylocke (without her upgrade), which allows you to meet the defense requirement for Psi Flail Strike with a single defensive activation.

Army of One adds 3 more instances of ready on top of Martial Arts Training.

Weapons Training also becomes very interesting since, combined with Ronin, we can raise Retaliate to 2.

If playing two-handed, I'd add a Defensive Conditioning to raise defense to 6 (without Martial Arts Training, which can then be discarded at any time to ready).