best way to end the full moon event is to kill only the mini-bosses which drop 50 (or sometimes 100) blood. That way one round yields around 220 to 250 event progess at average and it costs you only 1 scroll. The event can be completed in 15 visits of 5 minutes, totaling only 1h and 15 min !! :)
Underneath the map with all the mini-bosses. There are 4 different maps, once you get one, you know where the other 3 are.
|New Moon event - Varholm - positions of mini bosses|