In order to fight in Jump Ultimate Stars, you'll need to build a team. Teams consist of multiple koma (panels), with at least one battle character, one support character, and one help character.
Battle characters are characters that can participate in the battle. They occupy four or more koma. There is a limit to how many you may have in a team. The maximum amount of battle characters in a single team is four characters, 3 4 Koma characters and one 5 koma. Generally, The more Koma a battle character takes up, the stronger it is (and the more health it has). At the higher end, characters might change completely gaining new move sets.
Support characters are 2-3 koma characters that come out to help the battle character out, usually by using a special attack. Some support characters require a target, in which case a display will appear on the bottom screen asking you to pick which player to attack. If one isn't chosen, one will be picked randomly.
Help characters are 1 koma characters that give special abilities to the battle character they are assigned to. Some help characters (Specifically, the ones that increase the Max special gauge) Simply need to be in the deck to take effect.
Each battle character has three "friend characters" that when placed next to them, will grant them a health boost. These friend characters will remain secret until the two characters are placed together. At which point, the battle character will sparkle, and the friend will say something. After this, the friend name and the quote will be listed on the battle Koma's information screens. The amount of health gained is not affected by the size of the friend koma. Leader characters also have a small boost in health.