Note: These are based on my own knowledge and what I think
Minimum requirements:
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HotM 3
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A set of glacite armor
Head over to the Great Ice wall
The Ice Walkers has a 0.25% chance to drop the armor
TIP
Fight them with your pickaxe
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Breaking power 6 tools
I have listed the tools from easiest to obtain to hardest
(I'll talk about breaking power later)
First head over to the shop to the right of where you spawn in the Dwarven Mines
He will sell you then Titanium pickaxe with a breaking power of 6
This is by far the cheapest option for mining tool that can mine gems.
The next tool in line would be the "Ruby Drill Model TX-15" With a breaking power of 7
It's made from the forge
It's way more pricey and requires a good amount of grinding. This is meant as an upgrade from the Titanium pickaxe mentioned above.
It will take you a long time to get all the materials need but it's worth it!
The drill can later on be upgraded to increase it's breaking power
Last but not least is the Titanium Drill set
In my opinion they are not worth it if you're just going to be in the Crystal hollows
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Grappling hook
Having a grappling hook will make traversing a lot easier
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Enchanted leather
You will need Enchanted leather in order to craft a gemstone sack
When you enter the crystal hollows you will spawn in 1 of 4 areas randomly (Jungle, Precursor remnants, Goblin hideout, Mithril deposits)
All areas have gems that are specific to them with Rubies spawning in all of them
Everywhere = Ruby
Jungle = Amethyst
Precursor = Sapphire
Goblin = Amber
Mithril = Jade
Under these 4 areas you will find the Magma fields which is home to Topaz
When exploring you also have a chance of coming across the Fairy Grotto which contains Jasper
To be able to mine the Gemstones you need a tool with the appropriate Breaking Power
(Refer to the "Breaking power 6 tools" section at the top)
Tasks:
As you know there are commissions, you might have seen for example "Sapphire crystal hunter" In the hollows there are 5 Big crystals for you to collect. Each crystal is somewhere within their respective area and each has a unique task to obtain it
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Within the Jungle you will find the Jungle Temple. To gain access to the temple you must obtain a Jungle key which can be obtained in 2 ways
There is a chance for the structure containing the "Key guardian" to spawn within the Jungle. Killing the guardian will award you a Jungle key
You may also find the "Tribe village" within the jungle. In one of the houses there is an NPC selling the Jungle key
After obtaining a key and entering the temple you will be faced with a parkour challenge. There will be arrow traps on the walls and lava at the bottom. Failing the parkour will send back outside the temple and you have to pay another key to try again. Good luck!
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Somewhere within the Precursor remnants you will find the Precursor City. In the middle you will see a massive robot with an NPC next to it.
To gain access to the crystal you will need to gather 6 Robot parts from the automatons that spawn within the remnants. After gathering all the parts you submit them to the NPC next to the robot and he will grant you access.
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The Amber crystal is heavily guarded by the Goblin queen's Royal guard. You must find a way to sneak past them to obtain it
You must locate the goblin King somewhere in the Goblin holdout. After completing his request he will cover you with his foul stench. With this you can sneak in undetected and steal the crystal.
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The Jade crystal is probably the easiest one to obtain. In the Mithril deposits you will find the "Mines of Divan" Its basically a MASSIVE vault full of gold
Talk to 1 of the 4 NPCs next to the statues. They will give you a Metal detector. With this you must go to the bottom of the vault and find the 4 relics in the gold. (You will see numbers appear above your hotbar with the distance to the chest). Once you have the relics hand them to the NPCs and the crystal will appear.
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This one might be a little tricky to find. The Topaz crystal spawns within the "Khazad-dûm" which is an area within the Magma fields. This means it could spawn below any of the 4 main areas.
To obtain the Topaz crystal you must help kill the Bal. The bal is a big Magma cube that spawns in the Khazad-dûm every 5 minutes as long as a player is nearby. Once the boss is dead the crystal will appear.
Side note. As long as you are in the Magma fields you will accumulate heat. Once your heat reaches above 90 you will start to take damage eventually leading to death. Leaving the fields or standing in water will reduce your heat. You can also craft the armor from the Hardstone collection which slows down the rate in which you gain heat.
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Great! You've obtained the 5 crystals, congratulations. Now that's left is to submit them. The crystals can be submitted at the Crystal Nucleus.
The Nucleus is a structure that always spawns at 500x500 within the Hollows. It's the central hub with access to all 5 areas.
In the Nucleus there will be 5 statues representing the 5 crystals. Click on each statue to place your crystals.
After placing all 5 crystals some items will spawn at the portal.
Note
Do it again! Yes, again! After you've earned your loot you must collect all 5 crystals again to gain another set of loot. This can be done infinity, it all depends on you!