Channeled Pyroburst. A question on timing.

[frankthedm]

Channeled Pyroburst is an amusing 4th level spell, medium range, SR yes & reflex for half seen ordinary, but by tweaking the casting time…

If you cast this spell as a swift action, it deals 1d4 points of fire damage per two caster levels (maximum 10d4) against a single target of your choice.

If you cast this spell as a standard action, it deals 1d6 points of fire damage per caster level (max 10d6) to all creatures in a 10-foot radius spread.

If you cast this spell as a full-round action, it deals 1d8 points of fire damage per caster level (max 10d8) to all creatures in a 15-foot radius spread.

If you spend 2 rounds casting this spell, it deals 1d10 points of fire damage per caster level (max 10d10) to all creatures in a 20-foot radius spread.

You do not need to declare ahead of time how long you want to cast this spell. When you begin casting this spell, you decide that you are finished casting after the appropriate time has passed.

Now I got to wondering, if the caster does not fire off the pyroburst at the full round action point, can the caster fire off the pyroburst on his next turn before he spends any more time[actions] on the spell? Having to cook the spell for 2 round [that is not just 2 full round actions] does seem like a major opportunity cost that can be a major liability depending on how that first round of cooking went.

In fact, could the caster choose to fire off the full round powered pyroburst while it was not his turn [while it was still cooking]? I know that boosts the spell a bit to be able to fire it off as a sort-of immediate action while powering it up, but considering how big a target cooking this scalable fireball makes the caster, it might be reasonable.

And does it sound like “When you begin casting this spell” should have been "When you are casting this spell”

 

[Infiniti2000]

And does it sound like “When you begin casting this spell” should have been "When you are casting this spell”

Not even that is a proper rewording of that sentence in my opinion. Leave off the "when" clause: "You may decide when you are finished casting after the appropriate time has passed."

Given that clarification, I've answered the poll.

 

[Infiniti2000]

It should definitely not be an immediate action as I find that completely outside the scope of the spell. Requiring an extra standard action in addition to the full round (not just FRA) for a FRA 'casting time' is not substantiated.

Requiring either FRA or 2 round is certainly within the rules, I think, but given the clarification above, I think the more lenient interpretation is also within the rules. So, I went with the lenient interpretation.