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Fusion Cauldron

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Fusion screen


The Fusion Cauldron can be purchased from the Furniture menu. Placed in the Shop, it consumes 2 to 5 items to produce an item of higher quality with a certain chance. Using more items increases the chance of success. Using different items reduces the time taken. Gems Misc GemIcon can be used to complete a fusion immediately.

A Fusion calculator can be found here. Fusion Calculator

Success rates

Success rate when same item used
Initial Quality Slots used
2 3 4 5
Misc QCommonIcon quality 100%
Misc QGoodIcon quality 100%
Misc QGreatIcon quality 75% 100%
Misc QFlawlessIcon quality 38% 56% 75% 100%
Misc QEpicIcon quality 30% 45% 60% 100%
Misc QLegendaryIcon quality 25% 38% 50% 63%

Note: these numbers are likely rounded, so 38 is probably effectively 37.5 and 63 is probably 62.5.


Upgrading your Fusion Cauldron enables you to fuse items of a higher level and receive better quality items. You can also increase the number of slots for simultaneous fusions. (You can think of this as buying a second/third/fourth cauldron, but it's still represented by a single piece of furniture and the upgrades apply to all of them.)

Level Cost Coin Cost Misc GemIcon Upg Time Max Item Level Fusion Slots Max. Simultaneous Fusions Size
Level Lvl1Icon 1K --- Instant 4 3 1 3x3
Level Lvl2Icon 5K 125 2m 6
Level Lvl3Icon 10K 150 5m 8
Level Lvl4Icon 50K 175 10m 10
Level Lvl5Icon 100K 200 30m 12
Level Lvl6Icon 250K 225 1h 15 4 2 (1,000 Misc GemIcon to unlock) 4x4
Level Lvl7Icon 500K 250 2h 18
Level Lvl8Icon 1.25M 275 4h 21
Level Lvl9Icon 2.5M 300 8h 24
Level Lvl10Icon 5M 350 16h 27
Level Lvl11Icon 10M 400 1d 30 5 3 (3,000 Misc GemIcon to unlock) 5x5
Level Lvl12Icon 35M 450 1d 12h37
Level Lvl13Icon 100M 500 2d43
Level Lvl14Icon 250M 750 3d45
Level Lvl15Icon 500M 1000 5d504 (5,000 Misc GemIcon to unlock)
Fusion Cauldron


  • Mythical items can not be placed into the Fusion Cauldron.
  • Speculation is that the fuse time might be related to the craft time of the item listed as "best possible".
  • When a fusion fails, you lose only one of the items, picked randomly.
  • (To be verified) Fusion time is divided by the number of different items in the cauldron. 5 different items decreases fusion time by 5. You could fuse 2 As in 30 minutes, then two Bs in 30 minutes, but fusing A+B takes 15 minutes, then A+B another 15 minutes.
  • Fusing Misc QCommonIcon quality items to Misc QGreatIcon quality precrafts to sell at the 10x base gold cap will hardly make you more gold than if you sold the Misc QCommonIcon quality items to customers, at the cost of fusion cauldron time and missing out on player experience. For Misc QFlawlessIcon quality precrafts you will even make a loss. Only use your cauldron to fuse precrafts if you want to use them yourself or to sell them for gems.

Algorithm to determine fusion outcome - outdated

The following section is outdated and wildly different from actual results. Consider the example below where a common + great same item only has a 0.36% chance to produce a flawless.

By Jabe: Qualities are represented by numbers - (0 Normal, 1 Good, 2 Great, 3 Flawless, 4 Epic, 5 Legendary). max_quality is the highest quality put into the cauldron. possible_results is a list of possible results.

// Generate the list of possible results
For each item put into the cauldron:
  Add a copy of that item at its quality + 1 to possible_results
  Repeat for each quality up to max_quality + 1

// Generate a weight for each item
For each output_item in possible_results
  nearest_quality_level = the highest level of input items of quality output_item.quality, 1 if none exist
  item.weight = nearest_quality_level * (output_item.quality -> 6, 5, 4, 3, 1) / (output_item.level ^ (output_item.quality -> 2, 3, 4, 5, 6))

Randomly select an item based on their relative weights

Breaking that down for a normal recurved bow and a great recurved bow. Recurved bow is level 14.

possible_results = {good rec bow, great rec bow, flawless rec bow, flawless rec bow} (there are 2 flawless because you said it's a list, not a set)

good rec bow: nql = 1 (no good rec bow existed in the cauldron), weight = 1 * 6 / 14^2 = .0306

great rec bow: nql = 14 (1 rec bow in cauldron), weight = 14 * 5 / 14^3 = .0255

flawless rec bow: nql = 1 (no flawless in cauldron), weight = 1 * 4 / 14^4 = .0001

second flawless rec bow: same as above, weight = .0001

Normalized: 54.35% good, 45.29% great, 0.36% flawless.


  • With the very best luck in the world, always going for the lowest percentage and always succeeding, it theoretically would take 64 commons to fuse a mythical.
  • By playing it as safe as possible, always going for the highest percentage, it would take about 1500 commons to fuse a mythical.

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