How do I change the buff of Phoenix Fire?

How do I change the buff of Phoenix Fire?

I was using the Phoenix Fire as a base for subspell that allowed a Tornado to hurl boulders at nearby enemies every so often and I cant seem to change it's buff from that of the Breath of Fire. No matter what custom buff I put in the "Stats-Buff" field, it still appears as Breath of Fire. Can someone fill me in (if this is even allowed by the program) how to change the buff?

I don't think you can change the buff, I have never had success with it, same as the old Frost Arrows buff.