make the event "Hunt the fields" ... then it will tell you what mobs you must kill.
for example 100 Forest Guardians. then go and get 2 Poseidon scrolls.
this will be a double help for you. #1 coz youll get 2 Poseidon stamps, and #2 the "Hunt the fields" event have HP-MP heal potions.

last way is to get the Free Food NPC every day.
just remember NOT to sort the today day free food with the yesterday food, coz they will dissapear..