The mycelium pool. Players can add fossils to calcify them into enriched bones.
The Mycelium pool is found in the northern area of the Mushroom Forest on Fossil Island. Players can find Irene here, who will explain what the pool is used for.
The mycelium pool can be used to calcify Fossil Island fossils (unidentified or cleaned and identified) into enriched bones via a chemical process requiring both pyrophosphite and calcite crystals. To do this, players must add the fossils, calcite, and pyrophosphite to the hopper. Players should add enough crystals to the hopper so that the chemical process can occur. The ratio for calcite and pyrophosphite to fossils required to start the enriching process is not completely known; the pool can hold 28 fossils and 10 of each of calcite and pyrophosphite, however only 6 calcite and pyrophosphite are required to enrich 22 large fossils, with size of fossil affecting the amount of materials needed. When players have added enough, the message The pool begins to bubble will display in the chat box. Upon completing the enriching process, all unused calcite and pyrophosphite will be consumed.
Whilst the chemical reaction is happening in the pool, the calcite and pyrophosphite will begin to be consumed, allowing players to add more, although there is never actually an instance in which you will run out prior to the process completing. Players must, however, poke the bobbing fossils that surface around the pool, otherwise the fossils will become too exposed to air and dissolve.
A player using enriched bones on the strange machine.
Once the process progress bar has reached zero, players must open the sluice gate behind the Ancient Shroom and check the rinsing pool to obtain the enriched bones. Players must have enough inventory slots to collect all fossils at once. These are then used on the easternmost strange machine in the House on the Hill to receive Prayer experience.
Each tier of cleaned fossil provides an increasing amount of xp: small fossils provide 500 prayer xp each, medium fossils provide 1000, large 1500, and rare 2500 each.
One trip of calcifying and consuming fossils takes roughly 2 and a half minutes. At this pace, the xp rates you can expect for each tier of fossils are 312k, 624k, 936k, 1560k, respectively.
It is important to note that plant fossils can not be turned into enriched bones. If added to the pool, plant fossils will be instantly destroyed, and no products will be received, wasting the fossil. An important distinction is that the pool will always accept unidentified large fossils, even though there is a 50% chance that they would become plant fossils after cleaning. Therefore it is recommended to NOT clean large fossils if you are intending to use them for this process.
- The placement and appearance of the Ancient Shroom in the middle of the pool is a likely reference to the mushroom people of the Dark Souls series.