The buff Holy Persuasion, which plants on the converted unit, is currently purgeable. But doing so does nothing at all. The creep still is under Chen's control, and keeps its hp bonus.

1. Persuade a creep
2. Have a enemy cast a dispel spell on it (e.g. satyr purge)

Result: The Holy Persuasion buff on the creep disappears, and nothing else happens.

Expected: The buff should not be dispellable.

Or make it actually revert the ownership of the unit and remove the hp bonus it got.