Auras, and how they Work

[Draco_Lord]

So. I have a final boss ready to fight my PCs. And I have a question about Aura. I have prepared a customized big bad demon for them to take on. And I have given him Unholy Aura, as he is based off of a Balor Demon. I know my party has Holy Aura. Would a casting of Holy Aura just cancel the Unholy Aura around the demon for as long as the spell lasts? (As I want to rule). Or would it cancel out and replace, creating a holy aura for as long as the spell lasts?

On that note, if two Clerics are fighting, and one casts Holy Aura, then the other casts Unholy Aura, what would happen there?

http://www.d20pfsrd.com/bestiary/monster-listings/outsiders/demon/balor

[Spore]

By RAW Holy Aura and Unholy Aura do not end each other. And no, I wouldn't allow both spells to cancel each other out. While the benefits cancel each other out, the buffs are all defensive and make a final boss fight more interesting as bothe the villain and the party lasts longer and have to overcome more hurdles to actually hurt each other.

If you feel the Strength damage and blinded condition take away too much steam (both hamper the damage output severely) remind your cleric PC to prepare Dispel Evil so that he can dispel the Unholy Aura. If you do not like giving your players direct tips, have his deity point him towards smart spell choices (as the Strength damage stacks and might make a target unconscious while the blinded condition is instant worse but doesnt progress to be that fatal).

Especially as the Balor can Greater Dispel all buffs from you leaving them wide open for attacks.

[Draco_Lord]

Okay. That works for me. I just wasn't sure what would happen if they cast it, and got the countering part a bit mixed up, thought it meant forever, not as a counter spell. Thanks for the help!