You're foddering off Owain? You make me cry. :<
Anyway, Wrath is, of course, a good skill that's been around for a long time, and two other units have the skill.
Meanwhile, Owain is the ONLY unit in the game with Blue Flame, so I'd say to fodder him off for that, and of the two units you provided, give it to the unit you use/like the most, or maybe Ares since he's obtainable at 4* rarity.
Missed the limitation for Wrath, sorry. On the topic of Blue Flame though, I thought that both of those units would be pretty good for it. Since Elincia comes with Flier Formation, she'll usually be around another flier when she attacks. For Ares, I run a Vantage build. I just thought that adding 25 damage to an attack every turn would be pretty crazy, and guarantee that any opponent gets OHKO'd by Dark Mystletainn vantage in the enemy phase.
His IVs are "bad", but his actual stats are more than okay if built for it. Is he the absolute best sword unit in the game? No, but the wonderful thing about FEH is that you can use the units you like for the sake of liking them rather than only going for units because they're top tier.
With a +6 attack buff (from something like Atk Tactic, Odin's Grimoire, or any other +6 attack booster), he reaches 51 attack, 56 when near someone with Atk/Def Bond, 60 if someone near him has Drive Atk, and that's not even taking into consideration his Blue Flame and possible seal slots.
Fair enough. I do like Owain quite a bit as a Fire Emblem character, but I've never used his Odin in FEH simply because of the fact that he's just not as good as other blue mages I had, like Linde and Ishtar. In FEH, my goal has always been to build the best possible teams, regardless of how much I like the character. Props to you for your dedication to Odin though, that's impressive.
Definitely Blue Flame. Even if you don't have Wrath right now, Blue Flame is the more rare skill, and you might pull another Owain soon. Your chances of getting a character with Wrath has increased slightly anyways. Plus Blue Flame is like broken. I initially thought it was inheritable, but then thought it wasn't because it was so crazy broken.
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