  Using local operations and classical communication (LOCC), entanglement can
be manipulated but not created. However, entanglement can be embezzled. In this
work, we completely characterize universal embezzling families and demonstrate
how this singles out the original family introduced by van Dam and Hayden. To
achieve this, we first give a full characterization of pure to mixed state
LOCC-conversions. Then, we introduce a new conversion distance and derive a
closed-form expression for it. These results might be of independent interest.
