This is the 9973rd most frequent Polish word.
atakowały
"Atakowały" means "they attacked."
The verb 'atakowały' here refers to the action of 'attacking' performed by plural entities, matching the subject 'armie wrogie' (enemy armies).
Na początku wojny, armie wrogie atakowały przerażone miasto.
At the beginning of the war, enemy armies attacked the terrified city.
The verb 'atakowały' is used here to describe repeated actions in the past by wolves, a plural subject.
Wędrowcy opowiadali, że wilki regularnie atakowały ich obozy nocne.
Wanderers reported that wolves regularly attacked their night camps.
Here, 'atakowały' metaphorically describes the action of waves hitting the shore, applying to a plural subject in a past continuous scenario.