Collocations for foe - noun

bitter, dangerous, deadly, formidable, implacable
He knew that Carlton could be an implacable foe.

common
old
In the final the play against their old foes, Italy.

former
political

defeat, vanquish (figurative)
She had fought many battles, vanquished many foes.

fight

against a foe
to join forces against a common foe

friend and foe
His newspaper articles criticized friend and foe alike.

friend or foe
She was unsure as yet whether he was friend or foe.