Mermaid Ball

Moreau's Laboratory (Reservoir entry): use the Crank on the mechanical door off the Windmill Yard, follow the path up, go right at the fork, smash the crate (Sniper Rifle Ammo), cross the bridge and turn left: small wooden shrine in the NE corner.

Optional. "The Water Wheel" labyrinth, in the shed behind the Windmill Shack (SE corner of the Windmill Yard): Chartreuse Skull (20,000 Lei).

Available as soon as you leave the Reservoir with the Crank, until you enter the Factory.