The League of Assassins has been described as a group of assassins that have spent thousands of years eliminating people that were "dangerous to society". However, the only concrete activities we ever hear about are the times they destroyed entire cities.
(In fact, in some other adaptations, like the Christopher Nolan Batman films, they're not even called assassins, they're the League of Shadows.)
Have we heard of any actual assassinations being performed by the League of Assassins (in a medium where they are called Assassins)? That is, where a member of the League intentionally murders a single, prominent person.