"The owls are eating."
The accent on the i of "atroksi" doesn't mark the accusative ? How would you say "they are eating owls" then ?
The same way, actually, sort of. "Atroksia" is the "dāria" subtype of the first lunar declension, where both nominative and accusative plural are identical. I think to make the subject clearer you'd say "Pōnta atroksī ipradis" instead, if the subject wasn't owls.