Hero Stats
| Boon | + Atk | Bane | - Def |
|---|
Skill Set
Hero Build Overview/Explanation
All stats assume your Mercedes is +10 merged/flowered, with Atk asset and potential unlocked to 5 star. More preferable to have a Spd asset, but Atk is still good.
Let's get one disclaimer out the way: be prepared to fodder A LOT of premium units, because she's objectively a very bad unit by today's standards, and like the introduction on her page states, she requires a lot of babying. But for my fellow Mercie fans, this is for you... if you wish to go the extra 1000 miles, thanks to Groom Saul's debut.
This is a full-on versatile offensive and support build, filled to the brim with utility for many situations, and can fit her on just about any team composition. Units you'll need to fodder: Groom Saul (you'll need two copies minimum, unless you're willing to fodder even more premium staff units like Flayn and Winter Sephiran...), Sara, any Dazzling and/or Wrathful Staff 3 unit, and any 4 star staff units with the lower prerequite skills like Still-Water Balm, so you can save yourself the trouble of needing a 3rd or 4th Saul for Deluge Balm+ and Return+, or even another Sara.
Observant Staff+ refine is of your own preference, depending on if you have Dazzling or Wrathful Staff in B slot. This is crucial to her offense and requires you to use your head a bit, but 3 spaces in-between a lovey dovey pair is generous enough to give you leeway into positioning strats. Especially useful if any of your team mates have cardinal direction buffs, like Peony. I recommend teammates with Atk/Spd buffs; moreso the latter, since Mercie's a middling speed unit, and Observant + Atk/Spd Push gives her plenty of Atk as is to give her high damage.
A slot is technically more optimal to have Atk/Spd Solo (so you can ensure your S slot is free for a second one to bypass Push penalty damage), but that requires fodder outside of other staff units. However, Push and Solo are the same boosts... one just has a damage downside, and the other (solo) makes your positioning even more complicated. Push is generally safer.
You C slot could also be your preference. You could fodder a Brady for Infantry Rush 3, if you want to use her primarily for support. Lends herself really well to aiding Galeforce allies, if they lack Heavy/Flashing Blade or any cooldown acceleration.
S slot is entirely your own preference, depending on what you need the most. If your team isn't providing enough Atk/Spd for her, go for something like Atk/Spd Solo 3 or Even Atk Wave, or just do so to maximize her damage, since a good enough team can 1 turn or 2 turn clear anyway. Mystic Boost 3 completely offsets the self-inflected damage of Atk/Spd Push 4, so that's preferred if you wish to aid in her survivability in exchange for some damage. If you want her as primary support, Even Atk Wave 3 is still very versatile, though if you want better consistency and you don't mind that she won't get the buff, go for Atk Tactic 3.
As for team composition, you've got full freedom there. If you want to maximize her survivability from physical attacks, an A/D Near Save ally like Dedue is a huge boon for this (or fodder a Dedue/Gustav into an armor of your choice, like Brave Edelgard, though that's pushing it, since those two are premium, and Edelgard has better uses for that C slot). Peony is also great for on-demand buffer + refresher. Fallen Dimitri's canto via Murderous Lion also aids in Observant Staff positioning while keeping up a strong offense, though really, any Canto user is good for this.
This build won't make her invincible, but it'll allow her to survive the current climate and even go toe-to-toe with meta units, provided she's got the right support behind her (if you're dedicated to full offense). Still, don't let her bite off more than she can chew. She can still get easily one rounded on enemy phase by just about any offensive unit that's either high speed or attack... or both, lol. She's a great magical tank under these conditions, though.
