Possession potion

• Crafting process: Must successfully capture a spirit. 
• Rising saving throws: DC is unique to the captured spirit. The DC rises for each failed save to a maximum of 21.
• Duration: Until a successful save is made or the possession is ended in some manner.

This potion contains a captured spirit that will possess the drinker. When ingested the drinker must make a DC (Wisdom save) determined by the DM depending on the captured spirit. The behavior the drinker exhibits, while possessed, depends on the specific spirit captured. The drinker may repeat the saving throw at the end of their turn ending the possession on a success. Each time the drinker fails the save the DC increases by (1) to a maximum of (21.) Once the spirit leaves the drinker's body its soul passes on.

Components:

• Spirit 
• Soul stone