First, you will need to go to this location on the map.

Nobody at this location talks to you.

And scare the birds across from the river.

After that, look for the flying birds.

The birds will lead you back to the original location.

This time, a giant talks to you.

You have to climb up on the left side.

Duck to look inside the cave for giant.

Is the Giant outside? You have to throw fire bottles.

He yelled! the giant is invisible.

You can't interact with him yet.

So you have to throw more fire bottles.

You need to repeat until the invisible giant is dead.

Invisible giant is dead now! And you can loot him.

And then drop the invisible giant to pick up his hat.

It is the rarest hat in the game!

You have to pick up the invisible giant again.

And carry invisible giant down the cliff.

Drop giant and see if you can lasso him.

Be careful, he may call a bear to attack you.

Pick a giant up and carry him away.