[SolAndLuna]

Again, fairly simple one this time - The Coastal Squall (and presumably, other tomes like it) amplifies damage done with certain elements. While it does do so correctly with usual spells, like Evoker or Aquamancer, it doesn't seem to work at all in the case of youkai evokes.

Given that the exact wording on the tome's description is "+UL% Power to Aquarian Spells (Halved if not main weapon.);+UL% Power to Sylphid Spells (Halved if not main weapon.)", this doesn't seem like an intentional function of the tome, seeing as there is no other conditional in the description.

[renowner]

Unfortunately I posted a similar issue long in the past. All things that add to spell power, effectively add it to the weapon's power stat or something. . . And since Youkai don't use weapons. . .Well, Dev said its intended :/

Cast order also doesn't buff them.

[SolAndLuna]

It's really hard to take it as "intended" in either case. The description for the weapon only states powering up spells of the appropriate type, whether they use a weapon or not should only matter if the description states as much. Especially when there are other items where their effects work fine regardless of what is used, like The Kiss Farewell activating Auto Charge even if you defeat an enemy without using the gun, or even any weapon at all.

Ultimately, it's either a misleading description on a series of weapons that's hard to get, thus potentially wasting countless hours of someone's time and effort for nothing, or it's the weapon not properly adhering to its own description, which leads to the same issue. In either case, something should be done about it.

[renowner]

I completely agree, i'm only referencing what dev said in my own earlier reports.

[Neus]

It's just how Youkai evokes work currently. It may change in the future when Youkai are touched, but it is not a bug.