Multiclassed Oracle / Mesmerist Mystery and spell interaction question

[Nikolaus Athas]

Hi Brains trust,

I've been looking through the rules and the forums and I can't find any specific rule regarding whether or not the Heaven's Mystery Awesome Display would interact with the non Oracle spells cast by this character.

So basically if said character has this Mystery but casts Colour Spray from his Mesmerist spell list, does he modify the spell as per the description of the Mystery? Or does he have to cast Colour Spray from his Oracle spells?

Please show me a reference either way if possible (FAQ or the like if not a rule)

Many Thanks

[willuwontu]

Awesome Display wrote:

Each creature affected by your illusion (pattern) spells is treated as if its total number of Hit Dice were equal to its number of Hit Dice minus your Charisma modifier (if positive).

FAQ wrote:

General rule: If a class ability modifies your spellcasting, it applies to your spells from all classes, not just spells from the class that grants the ability. (The exception is if the class ability specifically says it only applies to spells from that class.)

Seems pretty open and shut to me, it would apply to your mesmerist spells.

[Nikolaus Athas]

Thanks That was what I was trying to find!