Just like all the other hunt quests this is no different, this time you're hunting Demon Hoppers and Cave Bats. Also as the soldier explains to you, you need 10 to complete the quest but you can reach for first place if you choose! If you leave the cave at any point either with threads or other such items your total will be fixed and you'll have to simply go to the Explorers Guild to report your results. So bring plenty of things to heal up with if you don't have a Medic on hand!