Bruised, Battered, Bloodied, But Still Standing

The kobold had 3 hit points left. Now, as the magical arc slams his body, crackling along the cell walls and sinew, he is at 0. A creature at zero hit points is staggered. Tired. Only one action per round.

Blood trickles out of the corner of his mouth as he engages in a dramatic soliliquiy that he shouldn't have the time for, but I'm the DM, darnit.

"Thought you were smart...you big mammals...think...so smart..."

His hand leaves the lever to your surprise.

"Heh, was faking..." he coughs. "I didn't fix the - HACK - valve...Someone did, but...I can't figure out..."

Both hands grip the crossbow now, and level it carefully.

"Not going...to..not make...a spectacle...out of me..."

He fires.

Not at Kaspar or at Castille.

At that lantern that the warforged left that you never looked at.

Keep in mind that a kobold's lair is ALWAYS riddled with traps since the little buggers are so good at making them.

Firing at a tiny object, AC = 7. The kobold shoots...and hits. Damage, hardness, yep. He hits and bursts it.

And the three bottles of alchemist's fire that the kobold had tucked inside of it some time ago, hoping that a stupid adventurer would pick it up without checking for traps first.

BOOM.

The kobold deliberately fails his save, and gets caught in the fire.

Castille is too far back to be affected.

Kaspar, make a Reflex Save DC 13. You have the Evasion class feature so don't worry about damage if you make the save.