Pulse Stone

Pulse Stone is a stone Mario and company were given by Moustafa to gain access to Dry Dry Ruins in Paper Mario. The nearer the player will get to the ruins the faster it blinks or "pulses". When Mario will find the right location, Mario will put it in a rock and the ruins will rise out of the sand in a marvelous cutscene.

In-game item description: The closer you get to Dry Dry Ruins, the faster it flashes.