Open the Mercenary Manual to check the completion degree of weapons, cards and other categories. Even in the case of single machine, the degree of completion can reach 100%. With the improvement of completion, you can go to the reward list to get paid items.

Mercenaries themselves have low blood, attack power and defense power, so they won't escape. They will kill monsters, and it's easy to die when they hit BOSS. Mercenaries can't be controlled, and they can't control their babies as freely as warlocks in World of Warcraft. Generally, mercenaries will follow you, and monsters will take the initiative to attack when they get close. Running is ok, but playing BOSS is not so easy.