What It Does

This single-use consumable applies Heart of the Immovable King (SAN drops 20% slower — the top of the standard sanity family, above Workaholic and Positive Thinker ) at the Pal Surgery Table . The surgery itself is free; the implant is consumed. Unlike the permanent "Implant:" key items, disposables stack in your inventory and each one covers exactly one surgery.

Sanity drains mostly at base while Pals work, so this is the ultimate worker quality-of-life slot: it single-handedly covers the extra drain from Demon’s Hand with room to spare, and it's the passive that makes a permanent Insomnia night crew genuinely sustainable.

Where to Get It

Disposable implants come from one place: the Ancient Relic Recycler . Every recycled Ancient Relic — any grade, including cheap Decayed ones — rolls exactly one implant from a 16-implant pool, so this one lands at 6.25% per recycle. Because it's one-and-done, spend it on a finished worker. See the Ancient Relics guide for the reward tables and the implants guide for how surgery works.