Does anyone know how to kill trolls after you knock them out but they don't die? I know spells will work, but is there anything else?

Trolls can be slain with fire or acid damage, as well as any magical spell damage done to their REGENERATING bodies.

You attain lots of Flamming Oil jars where you will encounter many, many Trolls. I don't even want to get into how sick the 2nd level is. Anyhow, simply throw a jar of flamming oil onto their downed corpse and they'll die.

Flame Blade cast by a Cleric/Druid for the final blow will also finish them off, as will any acid/fire damage as stated above.

-Syl

i.e. Have your mage memorize all the fire spells he/she can... burning hands and Az-something's Scorcher are two great ones.

After you've downed the trolls, have your mage stroll over and cast a fire spell, and you'll be treated to the Troll suffering an agonizing death!