I know we eventually get to max them all, but I probably won't even make it to the 3rd skill let alone level 100. It probably doesn't matter very much, but I'm torn between Ray of Light and Heart Attack.
Ray of Light people don't seem to enjoy it, but I like to find uses for it even if it's not practical. It does a good job of holding things back when they are clustered together especially. I generally have more fun using it than Heart Attack.
Heart Attack doesn't seem that useful to me, but really anything sprite related is just a small bonus. It's not like the sprites do a huge majority of the work. I do like the idea that it's a more obvious support skill and there are times when a few hearts could save you but then again it's usefulness seems stretched. Heart Attack also seems a lot more dangerous to use than Ray of Light and less likely to profit from the hearts/damage you receive. I guess it's more of a huge "maybe" of potentially helping your team mates?
Unless these two skills show a big difference upgraded compared to default levels, I think I'll just upgrade Ray of Light a bit. I'm curious if there's something maybe I don't realize yet about one of the skills or perhaps I'm right and it doesn't really matter what I do. Ray of Light seems fun at least, so that's probably the way to go regardless. I guess I'm really bored with hoarding my skills and like I said, I may never get to unlock Angelic Aura.
Sadly, Seraphynx is no-where near the utility of Maskeraith, and no-where near the damage of Drakon nor Maskeraith.
However, it is the clear-cut best defensive Sprite in the game. The Light Ray can wall enemies, keeping them away. The Heart Attack is self-explanatory. And the third skill makes you invincible, as well as anyone else inside the shield.
You unlock the third skill at Level 50, but don't worry about that too much. Seraphynx is good and fun to use, but definitely the hardest of the three to get used to.
On the note of Heart Attack, it's an amazing skill once you invest into it, especially in large groups of enemies where you can get 30+ hearts to spawn, which is very helpful in harder areas.