Boosts linked card's skill by X%【合体スキル】合体したスキルの威力を上昇させる
Spirit of the Supporter補助者の闘志
On straight+, boosts main card's Enhance skill by 20%親分が合体スキル持ちかつストレート以上のとき、スキル威力20％UP
Divine Flames of Immortality聖なる不死の炎
|アポロン, イフリーナ, 祓魔師ヨハン, フェニックス|
The original power-up and one of the original enhance cards, Ifrina is the arguably lesser half of the Elemental duo with her and Undine. Power-up is almost entirely a PVE skill, however in that perspective it's also possibly the best of the three types in that situation. Merely being an enhance card makes Ifrina a decent draw, and the fact that her sub skill is a renaming of Enhance Skill+ Lv. 4 (i.e. the best sub) makes her perfectly fine as a sub if you decide you don't want her actual skill.
In a lot of senses, however, she's an arguably worse card in every way than Mercurius. She has a worse super fusion, her stats are slightly lower, and while not as ideal as a sub-card Mercurius is more generically applicable. Still, considering that Ifrina is one of two options, you may as well take what you can get.
For more about enhance cards, view the page About Enhance Skills.
This is literally a carbon copy of Peridot skill, except with slightly different wording. As Peridot's subskill is the best, technically, sub skill for enhance cards, this makes Ifrina just as good. In practice, a +20% benefit is easier to get than the +35% of damage skill best-in-class subs, but while matching it is possible this does match on icon.