Bonebound -Forbidden Left-

Bonebound -Forbidden Left- is an unofficial fan-made mod that adds Osty from Slay the Spire 2.

Open the “Forbidden Grimoire” and summon Osty, the giant-like left hand.

Osty follows the player and grows gradually while fighting enemies.

Key Features

・Forbidden Grimoire
Using the grimoire consumes the item and allows you to summon Osty from then on.

・Following and Combat
Osty follows the player and automatically fights nearby enemies.

・Soul Level
Defeating enemies alongside Osty increases the Soul Level and teaches new attacks.

・Growth
By giving special items, you can grow Osty’s health, attack power, and size.

・Sacrificial Shield
Osty takes damage on behalf of the player using its own health.

・Recall
If Osty gets separated, you can call it back to the player’s location using a customizable dedicated key.

Mod Integration

Patchouli

If Patchouli is installed, you can obtain the “Singed Research Notes,” which describe Osty’s abilities and growth.

Fan Project Notice

Bonebound is an unofficial fan project inspired by the Osty from Slay the Spire 2.