The Ratling Boss is found in the southwest chamber of the Sewers, along with an assortment of six Ratlings. Equipped with a cannon, the Boss' blows can do heavy damage and knock you back a tile; fortunately, he won't shoot through his underlings, which can be a relief if they swarm around you.
When the battle starts, the room is sealed by a gate closing behind you; one of the Brass Keys scattered around the chamber will open it once more. If the enclosed space gives you trouble, you can use Invisibility to make your way to one of the keys without drawing their fire. Once outside, you can take on the Boss with more mobility, and even defeat him in one hit by using the ladders to drop on him from above.
Hamlet of StormbreachEdit
Shortly after your victory in the Sewers, a second Boss will show up in the Hamlet with an even larger group of Ratlings, Wargs, and even a Forest Ogre. When killed, he drops a letter explaining his presence:
To the mightiest and most vicious beast of them all!
Be it known that the trespassers are responsible for the death of your twin brother. They came to the island not a long time ago and already they have become a nuisance. Gather your kin and deal with them.
The Island Master