Probably Final Spark, but only because Marisa doesn't hold back. Nanoha prefers to make people listen, rather than snapping off snarky comments at smoldering corpses.
Eh, no. Nothing Marisa has is even near Nanoha's level. Her sparks don't have the risk of ripping space-time itself.
Also, Marisa does hold back. She isn't even allowed to fire of deadly magic due to the spellcard rules.
Marisa is very powerful among human, but she isn't really how fanon depicts her. I think it's a important fact that she faces of against youkai who could easily beat her in power-output despite knowing her weakness compared to them. That's what makes her so badass.
Kuji-kiri said: Also, Marisa does hold back. She isn't even allowed to fire of deadly magic due to the spellcard rules.
...Rules which she flagrantly flouts with her broom-charge spellcards. Everyone else just ignores her rule-breaking in that regard because it's just such a Marisa thing to do, and the key point of danmaku dueling is self-expression.
Anyway, I'm not really going to get too deeply into a powerlevel discussion here. Just firing that off.
