Bad IV Units: Are they Usable?

Lute is deff viable, mine is also -spd.
get her life and death, +3spd seal and threaten res. she will have 40spd with that setup before any buffs!

Performing Indigo Is viable with any iv tbh, you can easily make him into a brave lyn and Reinhardt counter (add bowbraker, Gronnraven and triangle adept), and with +hp IV and +5 hp seal (45hp) you can add panic ploy to him and make him a complete horse emblem braker! (he naturally has more hp than Lyn, Reinhardt, Cecilia, Olwen. Leo has a bit more but the seal will take care of it, xander by default has 44 hp so itll even affect him :)

I used my 5* catria as a Killer Lance+ fodder, soon we will be able upgrade it to slaying lance, so its even better!.

Lyn - definitely still usable.
Eldigan - works great. I have this IV on him as well and he tanks like a god. The most important thing is that his def wasn't affected.
Catria - works with this IV, but isn't really worth investing in (yeah she pity breaks me a lot as well).
Lute - don't have her, but she should be still kind of ok. A breaker B skill is recommended.
Inigo - the increase of hp levels out the loss of def and increases his mage baiting potential. Still will work well for the standard raven bowbreaker build.

Not sure how far you are but Catria carried me through early and mid game. +Def can make her a real flying tank. Had two builds for her in and out of flier emblem. My Lyn is +def but I guess you can turn yours into a glass canon^^ every Lyn is viable unless -atk

LYN

Lyn's stat spread is quite unoptimal at the moment. Unless you've a +Atk boon, she doesn't have many build options. Even a -Spd bane can lead to optimized build as long as she has this primordial Atk boon.

Thanks to the new skills and seals, she now have a few things to play around with, in order to salvage her weaknesses, such as Wrath for some burst dmg, Close Def seal to capitalize on her good def/res stats, Brash Assault seal is an ok alternative too although one thing people did NOT think about is her ability to exploit Deflect Melee 3 in 100% of the cases, thanks to her built-in desperation, if you equip her with Vantage as well, then she will always get consecutively hit.

In brief, I suggest you to wait to see her weapon improvement with the Refinery update, to see what very good combo we can patch on her, and maybe get a better IV set sooner or later.

ELDIGAN

First, let's mention that you've got the absolut worst IV set for him. BUT just like Lyn, he may benefit a lot from the incoming weapon refinery and become even stronger as he already is.

In fact, he is the 2nd star mounted swordman after Xander which is GHB unit (implying no IV set, limited merging), so he definetely have a lot of potential. Keep him in a corner of your barrack too!

CATRIA

Catria used to be a very decent unit, especially before inherance, as she was one of the few pegasus able to tank physical hits. Now we could say "she is 5* so that she can waste your pity rate from time to time". She is still an OK unit that you can use as a budget version of Tana and Cordelia for dmg dealing and F2P Valter for tanking and nuking.

LUTE

Lute is a bit overrated although her stat spread isn't bad, she is only as good as her Weirding tome is. Her stat-spread doesn't enable her to much versatility despite her powercreeped BST but she still have a bit of a niche along side (or a bit behind actually) Linde, Delthea and Reinhardt, as the trio of SS-tier mages.

All in all, Lute is still very dependant to her IV set, just like the latter trio of blue mage. There isn't much you can do to salvage that bad IVs since capitalizing on them would be worse than anything really. Just build her as if she had perfect IVs until you've get them.

P!INIGO

As a dancer, his main role is to support and that's why his IVs won't really matter. Plus, thanks to this polyvalent role there is several things you can do to salvage these lame IVs.

You could equip him with Poison Strike (and salvage blow skill+seal if you like too) in order to chip away a lot of HP from foes that would not counter attack him such as B!Ike (and so his surrounding allies) when you don't use him strictly for dancing/buffs. Otherwise if you rather have him full support, just go for Hone skills, Wings of mercy and such.

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That's a lot of typing, hopefully it helped tho..!

I use a +res -spd Inigo and works well with TA, Bowbreaker and Gronnraven+
And he is an event hero, don't sacrifice he.