Answer:

derats

Answer	Crossword Clue
DERATS	Emulates the Pied Piper
DERATS	Clears la the Pied Piper
DERATS	Clears of vermin

DERATS	Disinfests
DERATS	Purges, in a way
DERATS	Clears of vermin, as the Pied Piper
DERATS	Cleans up Hamelin, in a German legend