This serum transfers a homunculus's loyalty from one master to another. In order for this to work, the homunculus's current master and its master-to-be must each place a drop of their blood into the serum. When an appropriate homunculus drinks this concoction, it thereafter treats the master-to-be as its master. The change in ownership also causes the homunculus's alignment to change to match that of its new owner.
- Alchemy Manual
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