ToME: the Tales of Maj'Eyal

I have a very unusual idea for a talent that I don't think has been done before. I'm not sure if it's even possible within the framework of Tome, so I'll ask for some help.

The talent creates a frozen orb projectile that slowly travels forward, dealing cold damage to adjacent targets. That part is easy enough, however the second part is more complex:

- On activating the talent, the icon will be replaced with a 'Frozen Orb - Detonate' spell, similar to how Shivgoroth Form gets replaced by Ice Storm. However, there's no temporary buff, as the orb might last a variable amount of time depending on where it's targeted or if it hits a wall. Or perhaps there could be a temporary buff that is removed on the projectile vanishing?
- On using Detonate, an X radius ball of freezing cold damage will be targeted on top of the projectile, and the projectile while be removed, at the cost of increasing the cooldown of Frozen Orb by a set amount.
- When the projectile vanishes from reaching it's maximum range, detonating or hitting a wall, Frozen Orb will reappear on the hotbar.

Is this doable, or should I just think of a more straightforward spell?

I'd say make a temp effect with no duration; make it when the projectile dies it removes it and make an on_timeout for the effect that checks if the player changed level, if so remove itself.