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Mastercrafting Guide
By Anketam
An in depth example of how mastercrafting items works. Intended for those who are entering endgame and have a good grasp of crafting mechanics. This guide does contain minor spoilers on various items, enemies, and mechanics. This guide is based on the Beta 2.10.5 release and thus any updates to the game can OBE (Overcome by Events) parts of this guide.
This guide covers end game crafting of items and enchanting. As such this guide assumes some familiarity with the crafting and enchanting system. For this guide I will be using a Mastercrafted Glass Bottle as an example:

Note the stats on it. This guide will cover more than simply getting the Mastercrafted mark, but fully leveraging that quality level to make a piece of gear, item, or tool that is worthy of being called Mastercrafted.
Requirements to craft Mastercrafted
In order to get the Mastercrafted tier it requires high quality items, tools and near by items to maximize the efficacy rate and high amount of crafting skill. For maximizing the efficacy rate Mastercrafted items count as Exceptional items. To get a mastercrafted item with three properties the crafting skill needs to be at least at 100% and to get four properties 125%.

The Glass Bottle has a simple enough recipe:
  • Refined Sand x2
  • Limestone Powder
  • Cork
  • Lit Furnace
  • Clay Blowpipe

But here is what is recommended to maximize the chance of getting a three property mastercrafted glass bottle:
  • Exceptional or Mastercrafted Bronze Knife
  • Exceptional or Mastercrafted Iron Mortar and Pestle
  • Exceptional or Mastercrafted Clay Blowpipe
  • Exceptional or Mastercrafted Furnace
  • Exceptional trees
  • Exceptional or Mastercrafted Refined Sand x2
  • Exceptional or Mastercrafted Limestone Powder
  • Exceptional or Mastercrafted Cork
  • High Botany skill
  • High Clay Throwing skill
  • High Stonecrafting skill
  • High Woodworking skill
  • 100% Glassblowing skill
  • Refinement Tools

To get a Mastercrafted item you want good ingredients to get those good ingredients you will need high skills, good tools, and good base materials to work with. To start with: Refined Sand. Good Refined Sand and Limestone powder requires a high amount of Chemistry skill and a high quality Mortar and Pestle to make.

To get a high quality Clay Blowpipe and a high quality Furnace requires high Clay Throwing and Stonecrafting (though the furnace can be made out of clay, which is slightly bit better).

To easily get an high quality Cork requires Exceptional trees which requires a high amount of Botany or good luck when randomly exploring and happening to spot an already Exceptional tree. From there when an exceptional tree is cut down it will likely give Exceptional Tree Bark which with a high amount of Woodworking and a high quality Sharpened Items (Bronze Knife) can be made into a high quality cork.

Note that the sand plays a major role in the weight of the glass bottle. Sand loses 2.3 stones of weight when crafted into refined sand and its min weight is 2.1 stones. So it is possible to create exceptional refined sand that weighs only 0.1 stones. It is recommend to use Refinement Tools to reduce the weight of the Tree Bark to 0.2 stones since its weight also impacts the final product. Limestone is consumed in the making of the Glass Bottle and thus its weight has no impact on the final product.
The chance of getting a three magic property item is not guaranteed even with a 100% efficacy rate and skill. As such it is recommend to stockpile a lot of Exceptional Refined Sand, Cork, and Limestone before beginning. Note that not all items need to be Exceptional to have a chance of getting a Mastercrafted item. As long as the minimum quality of items is a mix of Superior and Remarkable a Mastercrafted item can result.

Since Glass Bottles are more troublesome in that they cannot be disassembled and reattempted, it is worth trying to use any Remarkable or Superior grade materials that happen to be laying around.

If Glassblowing is not at 100% equipping items that boost it to at least 100% works to get the three properties available. Also refining produced glass bottles that did not make the grade is a good way to raise the glassblowing skill (use a quickslot to speed up the refining process).
Refining and Enchanting
So after many failures you finally got a Glass Bottle with three properties, but that is only the half way point. Before doing anything else it is recommend to refine the glass bottle down to 0.4 stones and reinforcing it with glue and repairing it to give it some decent starting durability.

There are four potential properties bottles can have: Potency, Endurance, Featherweight, and Worth. Worth is worthless in this case since this item is too valuable to sell leaving the other three. As such there is only a 25% chance the glass bottle will have the desired properties on it.

So if the glass bottle does not have the perfect trifecta it is time to reroll the enchantment using Magical Essence. There are three ways to get Magical Essence:
  • Kill Ghost Pirates and craft it quickly
  • Kill Acid Spitter Demons and loot it off their corpse
  • Burn Skeletal Mage Wands

The last option is the easiest and recommend way. It is rather simple: toss a skeletal mage wand into the fire:

Patiently wait for it to burn and turn into:

Then use tongs' Grasp command to pick up the Magical Essence (assuming you do not want to get burned).

Since there is a 25% chance of getting the desired result it typically does not take too many Magical Essences to get the desire magical properties. Do not worry about the stats themselves that is for the next step.
Upgrading Magical Properties
Once the Glass Bottle has the three desire magical properties it is time to upgrade the item. Magical Aspects can be used to randomize the magical properties' strength, but this can only really go so far since the odds of getting max value for all three magical properties is too low. That is where Magical Extract comes in. When used it will randomly upgrade an existing magical property (with diminishing returns as the magical properties get stronger).

It requires:
  • Peat
  • Coal
  • Calligenous Scraps

Peat and Coal are easily gotten on Coastal Islands while Calligenous Scraps are a little bit more tricky to come by... you will need to hunt Void Dwellers.

The best place to hunt Void Dwellers is to dig around in the underground and find an isolate void tile like so (Cartography can be used to draw maps of the underground which can be useful to find potential void pockets too):

Once you find one you will want to start dropping in items one at a time that have at least 100 worth. Each turn an unknown random value is picked if the dropped item's worth exceeds that unknown random value then a Void Dweller will spawn. As such more valuable the item dropped the greater the chance of a Void Dweller spawning. Happen to have leftover treasure that is collecting dust in a chest? Throw it into the void. Realistically the most practical item is flour (with Worth enchantment) and Hardtack. Wheat can easily be grown in large quantities and so it is products are a good choice for throwing into the void. You will know you are doing it right if you see "You hear a faint ringing in the distance" appear in the logs:

Eventually you will be greeted by this guy who happens to have 666 health and no armor nor resistances:

It will attempt to flee when it gets bellow 10% HP thus it is best to summon it in an enclosed area since it is hard to chase it down and collect its loot if it flees into the void. Note if it does leave your looting range and you kill it with a ranged attack, the Calligenous Scraps can still be retrieved with a fishing rod (odds are the item will decay before the rod catches it). Calligenous Scraps decays fast so it is important to have Peat and Coal ready to go and it is a Master level recipe so high Chemistry is strongly recommended.

After using many Magical Extracts the bottle will have maxed out its magical properties and then it will be completed.