In Trynton, you probably want to help the Trynnies to get rid of the Rattkin Breeders. Now these are monsters doing monstrous damage; but they also have good loot available. Around Level 10, even earlier sometimes, you could be able to beat them (on expert); depending on your group and equipment it may be easier – or harder.
They are in a room with 3 Rattkin Archers, but these are no problem compared to the Breeders. So, I’m not going to write anything about the archers. Basically, if you have the Breeders under control, you have won the fight. So here goes:
They are weak to Fire and Mental Magic, so you should really try to spam higher level Insanity or Fear on them to keep them under control while killing them. (If you have the Jack in the Box for your Gadgeteer or the Siren’s Wail for the Bard, that is mostly a safe option). You can watch an example fight on expert difficulty here.
Otherwise they are doing really good melee damage and can knock your guys unconscious as well as poisoning them or paralyzing them – so watch out, kill them quickly and keep them under control. If you cannot kill them quickly, don’t take a chance and try to remove all negative status effects from you party as soon as possible as well as heal up. It will help you survive the fight.
It is recommended you use special equipment you found in this fight. Especially buffs will work well, like a Scroll of Haste. Also, distribute potions and sneeze powders on your party members in case of hp troubles or someone going unconscious.
Have fun beating the rats