An event that is quite versatile and strong and that may be easy to miss in its qualities. Often this event is used to try to finish an enemy summoner or champion, and that is a perfectly valid use, however, one should not miss that you don’t need to do something extreme for this event to still be worthwhile.  Often getting your third attack in is very risky but Ava may get an "extra" attack thanks to this event. 
Is it worth using this event just to allow Ava to get an attack where you would otherwise just get only two other attacks? Absolutely yes!  A 3 ranged dice attack for one event is totally worth it and you should indeed use this in such scenarios.