.. Getting past the fire beavers

Did I say they like bones? Maybe you can feed them a bone. ( You can collect bones from the spider web. Take at least three. )

Throw the bone to a beaver.

Go left from the dam, there's a ledge. A beaver will get into the position on top of the ledge.

You can now use the bone on the river. The beaver will dive after it.

Hmm.. good question. Well, the beavers are made of fire. And you have a...

...fire extinguisher!

When the beaver jumps down you have to use the fire extinguisher to extinguish it. You need to time it right. ( Use the extinguisher just after the beaver roars. )

Three. After that you can go over the dam with the bonewagon.