Forming a Team (Party) in GOGO Muffin. The guide includes information on team formation methods for main quests, trials, etc. is provided. Use this guide when forming a team.
Table of Contents
How to Form a Team in Main Quests (Co-op)
One Mercenary (NPC) Automatically Joins

In Main Quests, one mercenary (NPC) will automatically join without any special operations. The participating mercenary will be close in level to the player and will support combat using skills, etc.
Mercenaries Can Change Professions

In "Co-op" on the right side of the screen, you can see the team information for the main quest, and you can change the mercenary's profession by tapping on them. If you want healing, change the profession to "Priest," and change the profession according to the abilities you want.
It's Also Possible to Proceed with Other Players

On the "Co-op" screen, under "Invite Player," you can also form a team with other players instead of mercenaries. It's possible to co-op with offline opponents, and by setting the follow option, if one person moves on the map, both will move together.
How to Form a Team in Trials
Form with "Start Matching"

In Trials, by selecting "Start Matching," you can match with players who are trying to challenge the same trial and attempt it. If enough players are not gathered within the time limit, you will return to the matching queue.
Use Create Team with Preference

With "Create Team," you can form a team through applications or invitations rather than randomly. From the "paper airplane icon" at the bottom of the screen, you can also send invitations to the recruitment channel.
Join Others with "Other Teams"

In "Other Teams," you can join teams created by other people. You can join a specific team by entering the Team ID, so ask for the Team ID displayed at the top of the team screen via chat or other means.
Recruit Members via Chat

Many high-difficulty trials are hard to clear with random matching, so it's recommended to recruit members in advance via world chat or other means.
Mercenaries Can Be Included in Some Trials

In some trials, such as the Secret Realm Gap, it's possible to include mercenaries instead of players. These mercenaries are just strong enough to challenge the trial, so use them when you have strength to spare or when you can't gather enough people.
Team Size for Each Trial
Secret Realm Gap: 4 Challengers

The Secret Realm Gap can be challenged by 4 players. Mercenaries can also participate, so if you can win the Secret Realm by yourself, it's recommended to take mercenaries along to reduce recruitment time.
Desperate Challenge: 4 Challengers

The Desperate Challenge can be attempted by 4 players. Mercenaries cannot participate, so find players who want to attempt the same challenge and form a team to try it.
Great Dragon Operation: 6 Challengers

The Great Dragon Operation can be challenged by 6 players. Mercenaries can also participate, but their level is quite low, so if you want to deal more damage, try challenging it with 6 players.
Nightmare Rush: 4 Challengers

Nightmare Rush can be challenged by 4 players. It's a long battle with up to wave 24, and if your speed of defeating enemies is slow, you will lose. Mercenaries can participate, but it's recommended to challenge it with other players.
How to Form a Team in Expedition
Decide Team Members After Starting the Expedition

On the Brigade screen, you can challenge "Expedition Teams," which only brigade members can join. Select the expedition target, and after pressing "Start Expedition," you can select team members.
Brigade Members' Clones Can Be Added

In "Expedition Teams," you can fight with clones of brigade members in your team. The clones will fight automatically in place of the player, so it's possible to challenge even by yourself.