It is essential that you recruit the monsters that roam the islands of Draconia into your gang as they have special skills that will help you to combat the enemies you encounter and also find loot. This How to Recruit Monsters Guide will tell what you need to know to get the monsters to join your gang.
There are some monsters you will encounter in Dragon Quest Treasures that will join your gang automatically once you have progressed far enough into the story, but generally you will need to defeat them in combat in order for them to join you. Keep in mind that this is not a guaranteed occurrence, there are some monsters that will not want to join your gang despite being defeated.
To increase your chances of a monster joining your gang you should fire Buddy Bullets at it using your catapult. This is done using your controller by holding down ZR, pressing Y to cycle over to your Buddy Bullets, selecting them, and then moving the aiming reticle to the monster you are after. If you defeat the monster soon after hitting them with the Buddy Bullet your chances of recruiting the monster will be increased. During the Tutorial you will be given several Buddy Bullets, you can buy more at the shops found in different open areas or craft more at the Pellet Workshop at your gang's base.
Another thing you need to take into consideration when recruiting monsters is if your level is close or higher than their level there is a higher chance they will want to be recruited to your gang when you defeat them. The way to tell whether a monster is within your level range is by looking at the level and color of its name. Blue means they are weaker than you, White means they are at the same level range, Yellow or Orange means they are above your level range, and Red means they are way above your level range.
Once you have defeated the monster you need to return to your base and speak to Miss Cecily where you will be shown the requirement that needs to be fulfilled before the monster joins your gang. Typically, this will be retrieving certain materials which you will be able to find in the open areas, and food. If you press the X button on your controller while highlighting the monster in the 'Recruiting' screen you will be able to see a list of what materials they want and how many of each they'd like. If you select any of the materials a hint will appear for where you can look for them.
Take a look at our Best Monsters Guide to find out which ones are the best in Dragon Quest Treasures.
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