Ether Mine - the following locations have the highest spawn rate (20%) for Mystery Firefly: * east of Test Pit 2, by the passage that leads to a dead-end * at the center of the first forked pathway, northeast of Test Pit 1 * at the center of the forked pathway when entering Test Pit 1 * passage that leads to the Glowmoss Lake * passage that leads to the Observation Point * Test Pit 4