Purpose of the Doll
The doll in Prairie's room isn't just there for decoration or to attack just for fun. If you continually strike the doll with attacks, in time it will drop a "W Can." The "W Can" or Weapon Can refills all of the weapon energy for all of the Live Metals. The doll will only drop it if you don't already have one. So return to the doll after you use the W Can to get another one. Cutting the doll from its string makes obtaining the item much easier.