Since her auto-revive is tied to her LD overhead icon, that means even with an orb that full dispels going off she can still revive the entire party. It also appears that all characters revived come back with all the buffs they have at the start of a wave. You get 9 stacks with all 3 LD uses but each time you fall below 50% it also uses a stack to auto-heal and attack the enemy. I wouldn't recommend going out of your way and purposely die just to get revive or anything because you lose all the stacks and established buffs etc but it is there if you need it.
Also it is really funny to watch her posing on the ground even when it is just an auto-heal + attack.
I have no idea if that count as a KO on the scoreboard or no though, because that will require an unfinished stage to see if that criteria lights up or not. I seem to remember seeing some kind of changes to reviving not hurting your score as much as before when Rosa LD came out with Reno's LC, but I don't know if you can get through that criteria with auto reviving like Eiko does. Maybe I will clear an unfinished LC later and make an edit.
Edit: Tried it in a chaos level LC, it appears that you can indeed die, auto-revive and still fulfil the no KO requirement on the scoreboard.
Currently semi-hoarding EX+ ingot so she will be a back pocket character until I am sure the coast is clear for EX+ing more characters. Next up I am gunning for is 100% Papalymo.
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