The Crusher Caverns is an endgame activity that prospectors unlock by finishing quests for Osiris.
The Crusher Caverns consist of 4 main rooms and a subset of corridors and smaller rooms, leading up the Alpha Crusher boss.
In between the rooms are some loot and activities that needs to be done to proceed.
Orbital Cannon Beacon
A Orbital Cannon Beacon is required to open the Crusher Caverns by blasting the Forest Crystal Seal. Finishing Orbital Repairs Part 4 gives prospectors the ability to craft Orbital Cannon Beacon, as well as giving them one. However, finishing this mission is not required to be able to use a Orbital Cannon Beacon.
There are several bodies scattered throughout the caves, which supply Ammo, as well as Scientific Loot. The Alpha Crusher drops an Alpha Crusher Heart every time. The other creatures in the caverns also drop high-value parts upon being killed.
In the room after the Alpha Crusher there are several high-quality loot containers which function as part of the reward of the caverns. The Military Boxes in this room have high quality loot chances in it as follows
- Quest item
- 50% Nothing
- 50% Abyss Alloy
- Creature head
- A creature head is guaranteed, with the following chances
- After attaining a Orbital Cannon Beacon, prospectors need to visit the surface of Fortuna III and find the Forest Crystal Seal, a large green crystal surface covering the entrance, in the western part of Crescent Falls and use the Orbital Cannon Beacon on it.
- Once used, an Orbital Cannon laser will fire upon the Forest Crystal Seal, allowing prospectors to proceed through the first corridor, which contain 1 Heavy Strider. At the end of the corridor is a destructible rock-formation that needs to be removed using a Pickaxe or Heavy Mining Tool, which then gives access to the first main room, these rock-formations that requires removal will be found in between every section going forward.
- The first main room consists of 1 Savage Marauder, 3 Mature Rattler and 6 Heavy Striders. fact-checking needed
- After completing the first main room, prospectors will come across a room adjacent too it where they will have to jump between rock-formations in order to reach the other end. If they fall, or if they chose to go down to mine Focus Crystals, they'll be surrounded by Acid Ticks. In a small room, on the right side after the jumps, is some loot consisting of 1 Military Box, 1 Medical Case and 1 Jacket.
- The second main room consist of several Acid Ticks spawning right next to the prospectors when dropping down, several Savage Marauders and Mature Rattlers. Some of the Mature Rattlers will be up on high-ground on either side of the room when entering along with 1 Savage Marauder on the high-ground in the middle. By taking care of the Mature Rattlers on the sides first, prospectors can use the high-ground on the left to get out of reach for melee attacks, giving them an easier time. In the room there is a corpse with a loose weapon-spawn.
- After finishing the second main room and proceeding further into the caverns, prospectors will come across some Consumable Boxes containing a good amount of ammo of each type, 1 Hidden Stash and some Medical Cases along with a Jacket. After the first set of loot, prospectors will come too a crossroad with several Heavy Striders. Prospectors should clean up the area and lure down the Savage Marauder in order to take it out from the high-ground where they enter from. Going right in the crossroads leads to some loot consisting of 2 Military Boxes, 1 Safe, 1 Jacket, 1 Consumable Box 1 loose weapon-spawn and 1 Medical Case, going down below entry or straight forward will provide some veins of Focus Crystal. Going left allows prospectors to proceed towards the next main room, but going up here will trigger a wave of creatures to spawn consisting of Tick and Heavy Strider]s. If a prospector is able to get aggro on the Savage Marauder before going up to spawn the ambush, they can ignore them, otherwise they will come face-to-face with the Savage Marauder at the same time that the spawn occurs.
- The third main room consists of 4 Mature Rattlers and 4 Savage Marauders. Once the creatures have been alerted, a wave of Heavy Striders will spawn on either end of the small stream of water. The Heavy Striders will also spawn at every other Savage Marauder that is killed and can easily overrun unsuspecting prospectors. At the backside of the room are some Focus Crystal veins as well as 2 possible ways to enter the next main room by removing destructible rocks covering the holes. Beware that these lead directly into the last main room.
- As soon as a prospector drops down either entry-point from the third room, into the fourth and final room, they should quickly look around and move away as they will will engage several Acid Ticks, 2 Savage Marauders, 2 Mature Rattlers and multiple Heavy Strider]s. If a prospector is not careful while dealing with these initial creatures, they may also get the attention of the Alpha Crusher boss. After cleaning up the initial creatures, prospectors should go ahead and engage the Alpha Crusher, but should be aware that at around 80%, 50% and 20% HP, there will be spawns of Acid Ticks and Heavy Striders to deal with. Killing the Alpha Crusher will award a Alpha Crusher Heart and chance for normal Crusher drops, as well as a rare chance for a Alpha Crusher Head.
- Once prospectors are done with the Alpha Crusher and looting the creatures, they can proceed through one last rock formation in order to reach a Healing plant surrounded by a lot of loot consisting of 1 Loose weapon-spawn, 3 Military Box, 1 Safe, 1 Ammo Box, 2 Hidden Stash, 1 Briefcase and 1 Jacket. Along the corridor leading out of the Crusher Caverns are several veins of Focus Crystal.