A pistolero is a hired gun.
His style is called hit and run.
If you're his hit
You won't like it a bit.
You're kaput when his job is done.

Merriam-Webster Dictionary: kaput
Variant(s): also ka·putt /k&-'put, kä-, -'püt/
Function: adjective
Etymology: German kaputt, from French capot not having made a trick at piquet
1 : utterly finished, defeated, or destroyed