|This build aims to boost Maria's solid speed and not-so-solid attack (hence the need for an attack boon) to significantly higher levels, allowing her to snag kills effectively with smart positioning and buff usage.
Weapon: Both Fear+ and Slow+ are relatively accessible weapons with the maximum inheritable staff Mt of 12, maximizing Maria's offensive potential. Alternatively, Trilemma+ is equally strong and works with teams using units with Cancel Affinity 3.
Assist: The ideal healing assist varies by team needs, but Physic+ and Recover+ are both solid options in that the former is Maria's default healing assist and can be performed at a 2-block range whereas the latter heals 10 more HP at a time.
Special: Miracle is a useful defensive skill that can save Maria in a pinch. That being said, the newly released Windfire Balm+ offers an often useful Atk/Spd +6 buff to your team on activation and can be considered if one has the resources to inherit to Maria. Heal-boosting special skills such as Imbue and Heavenly Light work as always.
A Passive: Atk/Spd Bond 3 is an offensively valuable skill for healers, especially for the already decently fast Maria, who is now able to not only hit harder but also double opponents more easily. Atk/Spd Push 3 is an alternative but requires the use of some form of self-healing in order to be reliably utilized.
B Passive: Wrathful Staff 3 is a given for an offensive healer set, since it lets Maria deal damage to foes without the usual 50% staff damage penalty. This slot can also fit Dazzling Staff 3, with the Wrathful Staff 3 effect added onto the weapon via refine instead.
C Passive: Spd Ploy 3 and Res Ploy 3 both take advantage of Maria's decent resistance stat to make it easier for her to double and kill low-resistance fast units in the former case and kill tankier foes in the latter case.
Sacred Seal: Attack +3 patches Maria's mediocre attack up even further, letting her make more out of her other buffing and debuffing abilities shown above. Having assists heal more is a plus too.