Hidden items:
Destroy huts, tents, or other homes. Some of them will have hidden items such as Scroll of Town Portals, Potions of Mana, etc. Pick them up to use later.

Drunken Panda picture:
Successfully complete all the levels in the "Secret tower level" to see a picture of the Drunken Panda along with what maybe his daughter. Then in the next chapter, you can use him to help.