In Argentina "pateale el trasero" has a softer meaning than the american "kick his ass".
Also use with the meaning of Get Rid of her/him.
Culo, orto or ojete (but not trasero is use to mean that a person or situation is/got very lucky. Some synonyms, words or similar expressions can be culo , orto, ojete (,this one probably the rudest),
Used in Argentina as well
"Pegale una patada en el trasero o el culo que culo q tuvo en el examen, le preguntaron algo bien facil"