Chaos Machine

The Chaos Goblin stands in the middle of Noria, near the vault keeper. The official guides give his spot as (180, 102) or (180, 103); a fan wiki says (179, 101) and that you need level 10 to use him. Most crafting runs through him: item upgrades from +10, wings and capes, Fenrir, Ability Cards, fruits, Devil Square tickets and more. Most recipes use the Jewel of Chaos.

Since Season 18 the Equipment Upgrade/Craft button opens the Goblin Combination page. Register the main item and the other materials from your inventory are added automatically; materials with + and − buttons let you set how many to use, and the help page lists every recipe in detail.

Since Season 18 each wing level is made in two steps: first a Wing Divine Object, then the wing or cape itself. A successful combination gives a wing or cape for a random class.

• Wing Divine Objects stack up to 50 and can be traded, sold in a personal shop and stored, but not dropped or sold to an NPC.
• Season 18 removed the recipes that made Condor's Feather and Garuda's Feathers, and Rexmilon's Seal no longer drops or works for Lv. 2 wings.

More about each wing is in Wings.

Before the Season 18 rework, a fan wiki describes these steps. They show how risky the machine has always been:

The Fenrir mount is built in three stages. Splinter of Armor, Bless of Guardian and Claw of Beast drop in Crywolf. Rates are from a fan wiki:

A Horn of Fenrir can then be upgraded with 5 Jewel of Life, 1 Jewel of Chaos and at least one +4 item with option +4: a weapon makes the Destroy version and an armor piece makes the Protect version. The Illusion version comes only from Castle Siege or events.

Upgrades from +10 to +15 are also made here, and a failure destroys the item; the jewel counts and Zen costs are in Item Upgrade (+1 to +15). An older official guide adds that a Talisman of Chaos Assembly placed in the machine keeps the item from vanishing, though it falls back to +0.

A convenience update added mass combination: you can run several of the same recipe at once, paying materials and Zen for each, with success rolled separately for every one. Charm-type items cannot be used in it.