Help understanding what is going on in a battle

[jimbojones1971]

Help in understanding what happened in a battle

So I've got a problem that I don't understand and I was hoping someone could explain to me what is happening.

The game background is as follows:
* Early Age
* CBM 1.84
* Dom patched to the latest version
* Llama's patch to CBM 1,84 (to cater for the latest version) has been applied.

I am playing EA Ermor. This is a battle with Kailasa.

I've got a mage with F3. He's kitted out with:
* 5 fire gems
* one astral pearl
* ring of fire resistance.

He's also got some fire immune followers, and some chaff.

My battle plan is to cast the following spells:
1) Power of the spheres (100 fatigue - burns the astral pearl)
2) Phoenix Power (20 fatigue)
3) Fire storm (500 fatigue - burns the five fire gems)

Part 1) works as planned. After casting power of the spheres my mage goes to F4, and uses the astral pearl. He still has the fire gems.

But with Part 2), when he casts Phoenix Power, he burns 4 (!) of the fire gems. He does indeed go to F5, however.

At this point of course, he no longer has enough gems to cast Fire Storm and it all goes to heck in a handbasket.

I'm really not quite sure what is happening here, and I'd love to get some help in working it out.

I am happy to provide my turn file if that is of use (as long as you aren't directly fighting me in the Statue of the Art).