Got this Winter Lissa during the legendary hero banner, and well shes +atk -def. I feel like her attack makes up for the defense bane but I'm too sure, any second opinions? Also what would be a nice build for her if she is worth keeping.
She has so many stats and they're evenly enough distributed that any IV is workable, especially with armour B-skills. Like, some people would say -atk is really bad; I think slaying+ignis/glacies would probably make up for it.
What's her role on the team, and are you trying to avoid giving her expensive skills like DC/steady breath?
Slaying axe+def, ignis, QR, keep bold fighter. Very simple and will work quite well. For an A-skill you have almost the entire spectrum to choose from - death blow if you want player phase, close def if you want enemy phase (stances are also reasonable), brazens if you want dual phase (but most of the time you will lose QR by the time they activate) or bond skills.
Or if you run spd buffs on the team, handbell+spd, aether, QR. Same choices of A-skills but don't use brazens because this build tries to stay at high HP. She'll get her spd into the upper 30s if not low 40s when the buff and ally support are added in, which makes her hard to double without bold fighter.
You can take inspiration from this, this user built her like this. Expensive, but she can tank many hits as she has 49 Def in the enemy phase. If you build her like this, you should reach 43 Def in the enemy phase.
Just like Seeker stated, try not to give expensive skills, this user have their W!Lissa SB as she has a Def boon.
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