With Rejection no longer an issue, I'm thinking that one-shot aggro will make a comeback. It's no coincidence that both Astaroth's and Ragnar's support carry two of our girl's symbols.
Origins Unknown and TWoP are your bread and butter for an Earth build, and you might as well mulligan if you don't draw either of these. Brooding and Hungry for Battle provide renewable pumps if you prefer to string out several attacks, but when I have tested her out, she has been more consistent with one big nasty attack. The good news is, both augment Origins Unknown. Same goes for Blinding Rage (somewhat diminished in utility in the post-ban world) , Tae Kwon Do Zephyr, and Enraged Golem.
Without the Owl to take care of No Memories/Holding Ground and other party poopers, it boils down to Program Malfunction and Inhuman Perception.
Attack-wise, I haven't been using Cobra Blow, because I've been worried about consistency. Only having 16 attacks is a little risky, and you honestly can't rely on Leona's damage pump ability, but by adding Cobra Blow to the mix, there are effectively four fewer chances for it to trigger. Its 2-check also worries me. While it's never a good thing to fail checks on the first turn, she's already making a huge concession with that squishy vitality. Slash Elbow is amazing with her, as she satisfies its condition as a damage pump. Consequently, every attack in my build is a mid zone: Hades Axe, Backhanded Axe Slash, and Hades round out the lineup.
Actions are how she really kills once either Origins Unknown or TWoP hits the board. Berserker Rage, Genocide, Slash Elbow, and Through the Defenses all add up, and can be quite lethal IF she goes off. I play her as if the game only lasted 3 turns, chewing up my own tiny vitality with Brooding and Berserker Rage for that extra push. When she works, it's a thing of beauty... like blunt-force trauma.
A tie.