If your DM is cool with BoVD rituals, you could probably swing a Ritual Sacrifice -> Agony vial at a DC25 or 30. Compare to Divine Power spell granted.
Additionally, metamagic rods are handy for buffing up Mystic Lash as well.
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My background for such NPC characters came about as follows:
Initially I played the party cleric as a Vow of Poverty ex-Monk / CG Cleric of Sharess / Sacred Fist (Travel/Trickery)
In accordance with Sharess being the saucy deity that she is, when the character was retired he went on to found his own free-love brothel. His commitment to VoP compelled him to donate away his adventuring fortune to the strumpets of the city, and those that were into their job were welcome to stay on and work for donations. Recruiting for Sharess
(I became the new DM) Inevitably the party left, picking up a new cleric (the former DM), and they left the city to pursue another adventure. Upon a return from adventuring, they visited their friend. Little did they know, the girls greeting them were infiltrators from the church of Loviatar, who were not too pleased about the competing business.
I had the advantage that my players can be pretty gullible, and thus had no suspicions about what they thought would be a routine visit to see their friend. The ambush consisted of them being drugged by Agony (for stun), exposed to Symbols of X (strip, body painted), and touch attacked by various spells and domain effects. It ended up being a really nasty fight for them