Felicia

I am currently building an all felicia team and have experimented on the various builds i can give her. This particular one is meant as a support/tank unit. With 50hp and 39spd she’ll be able to tank a hit or two even though she is unmerged. When she is merged she’ll have 54hp or 59 if summoner supported. Which is actually a lot and she should be able to proc infantry pulse on most units. She can also run the panic ploy seal along with it but it’d mean she loses 5hp making her have 45 unmerged or 49 max merged. Her hp can also be increased through blessings as the bonuses stack depending on how many legendary heros you have. For example having 1 fjorm will give her +3hp and +3spd, but having 3 will give her +9hp and +9spd making her much more tanky having 59hp unmerged and 63 max merged or 68with summoner support. Anyways i dont know how viable this build is but it’d definitely be crazy to see this in arena.

The general anti mage Felicia build that has started to become popular as of late. Felica is one of my favorite characters and I’ve been using her since the start. Originally I was having trouble using her since her atk was so low but as soon as skill inheritance came I was able to improve her. And now with the mage meta and seals she can reign supreme in the mage killer niche. I usually run into a team with at least 2 mages every time I play arena, she can kill them easily and her special does around 36-40 dmg (depending on if she is merged) when it procs making her 1 shot around a third of the cast even if she does 0 base dmg. Raven tomes + Triangle adept were a problem for a bit but with felicia plate and its special effect she no longer worries about that as she can proc glacies so long as she doubles. I recommend having someone with fortify res just to boost her through the roof. Anyways if you wanna see her in action check out my twitter @genjisfatass and look at my pinned tweet. Its a thread of the times when she has done her job well, the more recent ones are when she her plate equiped.
Just to update this as now the meta is dragons/armored units she can still defeat most of them but just barely. Regardless she is a pretty solid unit to have even if its to just deal with mages

Merge: +0
Seal: Attack +3 (43 Attack while equipped; 40 without)

Player Phase Felicia

Alternative Skills:
Weapon: Kagami Mochi+ (Res) / Kitty Paddle+
Assist: Reciprocal Aid / Draw Back
Special: Glacies
Seal: Distant Def 3

Pros:
+ With her newly acquired Felicia's Plate, she can expose her target's lowest defensive stat and deal good chunks of damage there
+ Incredibly fast, many targets will have hard time escaping her wrath
+ Once refined, Felicia's Plate becomes a major threat against mages as her Special cooldown accelerates quickly when in combat with them
+ Can also effectively run Kagami Mochi+ or Kitty Paddle+ in her disposal

Cons:
- Has abysmal Attack, she'll have hard time dealing damage outside of her Special trigger and not having access to Felicia's Plate
- Has low Def, thus she is easily taken out by powerful Brave Bow users and almost any melee users (and of course, Poison Dagger+)

IVs: +Speed/Res -Def
Weapon: Felicia's Plate with Effect forge
Supports: Any Movement Skill
Special: Iceberg
A Skill: Fury 3
B Skill: Seal Atk/Spd 2
C Skill: Spd Smoke 3
Seal: Atk Smoke 3

The ultimate debuffing Felicia. With Seal Atk/Spd 2 and Spd Smoke/Atk Smoke, she debuffs the target by 5 in offensive stats and 7 in defenses, and all other units within 2 squares get a flat -7 to all stats, making them incredibly weak. Felicia's Effect forge is used just to increase her damage output by making her special charge quicker when under attack from her weak targets. Iceberg since it's able to trigger in one round with Felicia's Effect forge.The support skill doesn't really matter at all. It can be anything you'd like, but a movement skill is preferable, as this Felicia will usually want to attack, but a movement skill helps get her and her team up to the battle faster, or abort the mission.

Boon/Bane: +Def/-Res
Weapon: Felicia's Plate (+Eff)
Support: Ardent Sacrifice / Reposition (if using Cancel Affinity)
Special: Iceberg / Moonbow / Glimmer
Passive A: Atk/Res Bond 3 / Mirror Strike 2 / Death Blow 3
Passive B: Desperation 3 / Cancel Affinity 3 / Bowbreaker 3
Passive C: Breath of Life 3 / Savage Blow 3 / Versatile Spur/Drive skill / Res Ploy 3 (if using Def Ploy 3 seal)
Seal: Atk Ploy 3 / Attack +3 / Breath of Life 3 / Def Ploy 3 (if using Res Ploy 3 C skill)
Summoner Support: She doesn't need it more than other units, but if you have to then by all means marry your waifu.
Ally Support: If she's using Desperation, use someone who can deal with Raven Tome users. If she's using Cancel Affinity, use someone who can buff up her Atk and/or Res.

Sweet Mother Mila the damage she does...finally the day when no one laughs when I tell them my Felicia took down a full-HP Camus without activating a Special. Because of her new weapon and its Forge upgrade (but most specifically its upgrade), she now has the ability to take down foes in one battle where she did literally no non-Special damage before. It's amazing...she's amazing. Felicia not only rose from the bottom of the bottom, but she's now one of the units you have to watch out for. She's now one of the units that shapes the Meta, and it makes me so happy.
Moving on to her skills, you definitely want to go with the Effect Upgrade of Felicia's Plate, since that offers Heavy Blade/Warding Breath CDR against Tomes which makes her even more of an anti-mage. Because of this, you want her to have a lower-charge Special instead of Glacies to make the most of that, so go with Iceberg (to make use of her high Res) or Moonbow (for the guaranteed 1-battle Moonbow). I would take the former against the general populace, but Moonbow will offer you so much more against Tome users. If you're feeling lucky, Glimmer is another option seeing as she's going to target the lower of her opponents' defenses, but she won't be able to handle balanced-defensive units very well at all.
As for her Passives, Atk/Res Bond makes the most of what she has. You would have to sacrifice a NY!Takumi for it, but combined with Ally Support you're looking at a huge increase in damage. Desperation, combined with Ardent Sacrifice as her Assist to get her within its HP threshold, will let you deal with targets that can counterattack you far more easily. Breath of Life is her natural C, and it's a great team-healing option if you lack a healer (especially since if you are making use of Atk/Res Bond, you will be proccing BoL).
As for her other options, Mirror Strike 2 is a more accessible alternative with 1 less each stat and lack of Enemy Phase usability but lets you rely less on hugging allies, while Death Blow 3 is very accessible and has 2 more Atk than MS2 but does not increase Res. If you're taking Moonbow or Glimmer as her Special, consider Death Blow 3 as her A skill. Cancel Affinity 3 is a very safe option that lets her deal with Raven Tome users, at the cost of less initiation safety; if you're taking this, Atk/Res Bond will be your best friend here as its effect lasts through the Enemy Phase as well. Bowbreaker 3 is a great option as well for dealing with Bow users such as Brave!Lyn and Jeorge that would likely destroy her on a counterattack. For her C skill, you can replace BoL with its opposite for splash damage on defensively-balanced foes or just give her a Spur or Drive skill. I wouldn't give her a Hone skill unless you plan on her ally straying from her side.
For her seal, Atk Ploy 3 is her best option for safer initiations...what's great is that if she can proc Atk Ploy on a foe, chances are that foe will be taking some fine damage from her Plate. You can also take both Res Ploy C and Def Ploy seal instead so that she doesn't need to make a primary attack to lower their defenses, but it would cost you a Sonya, Lute, or Gunnthra for Res Ploy and each of them are pretty rare summons. Attack +3 is an option if you want more damage from her weapon, and Breath of Life 3 stacks with its duplicate C skill for even more ally-healing.
The Ally Support you want to go with really depends on what build she has. If you're going the Desperation route, she'll have trouble against Raven Tome users so you want her AS to have an option against those. If you're going with Cancel Affinity then she will have less safety on initiation (especially against Distant Counter users), so you'll want to give her an ally that can boost her Atk and/or Res so she can deal as much damage as possible before dying.