Lost Artifact is an unlockable trinket in Fiend Folio, a mod for The Binding of Isaac.

Upon clearing a room, spawns 1-3 Fairy familiars that can be of 3 different types:

Little Fairy Fly (74.5% spawn chance): loosely follows Isaac. It deals 10% of Isaac's damage on contact, and occasionally shoots tears that deal 50% of Isaac's damage. Occasionally rolls a 20% chance to launch itself into an enemy, dealing 2x Isaac's damage and dying in the process. This chance is increased by +20% after each unsuccessful roll and after every room cleared.

Round Fairy Fly (24.83% spawn chance): tends in to move diagonally around the room, but homes in on enemies when close. It deals 25% of Isaac's damage on contact, and swells up while dealing damage or after clearing rooms. After swelling up to the maximum (usually 5 stages, but there's a random factor associated), the fairy will launch itself into the nearest enemy and explode into a circle of 8 tears that deal Isaac's amount of damage.

Big Fairy Fly (0.66% spawn chance; 40% in Boss Rooms; 20% in Miniboss Rooms): slowly moves towards enemies, dealing 10% of Isaac's damage on contact, before performing a Giga Bomb explosion that deals 100 damage in a radius, but can also damage Isaac for a full heart of damage if nearby.

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The chance to spawn an additional fairy is 20% with base luck. If a Big Fairy Fly is spawned, no additional fairies will be spawned for that room.

Spawn chance of Round and Big Fairy Flies, as well as additional flies, is affected by luck and boosted up to 40% with 28 luck, or lowered up to -25% with -10 luck. This is not a direct spawn percentage, but an increase/decrease from the original.

Fairies are spawned in random colors and sizes. The size does not affect their damage output.

The fairy tears inherit Isaac's tear effects, but also the following tear types:
• Brimstone / Azazel
• Dr. Fetus / Epic Fetus
• Spirit Sword
• Mom's Knife
• Tech X
• Technology

Additionally, each of the following tear multipliers will cause fairies to shoot +1 tear: 20/20, The Wiz, The Inner Eye, Mutant Spider.

Fairy tears inherit Isaac's shot speed stat.

Fairies deal contact damage 2.14 times per second.

Fairies will dance around the trinket when dropped on the ground.

Fairies have random names that are visible if the Show Room Names option is enabled.

Complete The Gauntlet challenge.

The following special synergies and interactions for Lost Artifact have been documented.

* Note that not all possible synergies and interactions are listed here.

• Check out the trinket description on the mod's external Wiki.
• Download Fiend Folio from the Steam Workshop.