I took an axe, but when I did, the ground lowered beneath me.

Hint 1 of 5:

Look around.

Hint 2 of 5:

There is a small passageway at the bottom of the room.

Hint 3 of 5:

A very small passageway.

Hint 4 of 5:

If you wait for a bit, you will morph into lizard form.  You can go up this
passageway in that form.

Hint 5 of 5:

Then, if the room at the top of the passageway is a dead end, look for a way
to open a wall.