  We consider the transformation of multi-partite states in the single copy
setting under positive-partial-transpose-preserving operations (PPT-operations)
and obtain both qualitative and quantitative results. Firstly, for some pure
state transformations that are impossible under local operations and classical
communication (LOCC), we demonstrate that they become possible with a
surprisingly large success probability under PPT-operations. Furthermore, we
clarify the convertibility of arbitrary multipartite pure states under
PPT-operations, and show that a drastic simplification in the classification of
pure state entanglement occurs when the set of operations is switched from LOCC
to PPT-operations. Indeed, the infinitely many types of LOCC-incomparable
entanglement are reduced to only one type under the action of PPT-operations.
This is a clear manifestation of the increased power afforded by the use of
PPT-bound entanglement. In addition, we further enlarge the set of operations
to clarify the effect of another type of bound entanglement, multipartite
unlockable bound entanglement, and show that a further simplification occurs.
As compared to pure states a more complicated situation emerges in the mixed
state settings. While single copy distillation becomes possible under
PPT-operations for some mixed states it remains impossible for other mixed
states.
