Wonder Boy III: The Dragon's Trap/Mouse-Man

Back in the pyramid, head down and grab another Key (it's always useful to have an extra one) then stick to the floor by jumping and pressing the appropriate direction. Head back towards the well you came in by and, still clinging to the ceiling, go past it and through the door. In here you'll find some good loot and a shop selling the Dancing Shield (430 gold). If you don't have enough Charmstones you may not be able to buy it. Anyway, go in the door to the far right then through the door marked "Return". You'll end up back in town.