I know that almost all unit can be useful if are used under certain conditions. but in this cases who good can be Arvis.
for Someone with 5* Arvis, with what frequency do you use He or for what requirement is builded/used?? do you recommend to promote to 5*
For Healer actually I use Masked Mart and Fae (Reciprocal aid/ Renewal)
Arvis is hella good. His main role is as a debuffer since his high res allows him to ploy almost every unit in the game. So if you have a spare Deirdre that you don't use, fooder her Speed ploy to him then give him Def Ploy ss and he'll safely debuff all stats to anyone that has less res than him. Also run fury 3 in his Slot A, his default B slot and give him Ardent Sacrifice and Iceberg. This is basically his only build and it works amazingly well
Arvis works very well as a combat-capable healer who provides some additional debuff support. All he really needs on top of his base kit is Fury, Ardent Sacrifice, and maybe a different special. In addition to his support capabilities, he gives Tharja a run for her money for the position of best offensive red tome outside of 5* exclusives.
Arvis is a really good -Ploy bot and pseudo-healer, with good damage-dealing potential to boot.
His default tome Valflame and C-Skill Def Ploy debuffs for -4 Atk/Res and -5 Def, which is incredible. If you replace Def Ploy with Spd Ploy and make his seal Def Ploy, then he debuffs every single stat of any enemy in his range, provided that his Res is greater than the enemy's.
His recover ring also grants +10 HP every turn (rather than every 2 turns like Renewal), so he can recover an ally's damage from skills like Fury or Celica's Beloved Zofia, Alm's refined Falchion, etc. with an Ardent Sacrifice. You can run Fury with Recover Ring on Arvis and turn him into a good mage that can attack or provide better support, while pretty much removing the HP loss due to Fury.
If you already have a good Red mage, then you could hold off on him, but his utility is too good to pass up in my opinion. Even if you run him on your Arena core, he still does well for in-game content or Arena Assault. I personally promoted him because I liked his design and play-style.
I +5 merged my Masked Marth with her typical medic/bruiser set alongside Aether + Heavy Blade and she's been an absolute MVP for me, constantly sitting at max HM.
And having said that, I still use Arvis all the time for PVE and Arena Assault content. He is an absolute beast at clearing out units with his amazing skill set and the supportive power he brings to the table with his Recover Ring and potential quad-debuff is insane.
For builds, here's a rough template,
Weapon: Valflame
Assist: Ardent / Draw Back
Special: Iceberg / AOE (for extended modes) / Glacies
A-Slot: Fury
B-Slot: Recover Ring
C-Slot: Spd Ploy / Def Ploy
Sacred Seal: Quick-Reposte / Def Ploy / Speed +3 / Attack +3 / Res +3 / Fortress Resistance 3
Until you go out and use him, you won’t understand how much fun he is to use. He heals 10 HP every turn, so you don’t have worry about fury chip damage, and if he sustains a big hit he can heal it off in a couple of turns. He was also a turning point for me in realising that red mages are completely undervalued and are actually incredibly useful in the current arena meta where brave ike and green armoured units have begun to dominate the green colour slot on teams
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