https://www.gamespot.com/articles/dragon-ball-fighterz-guide-how-to-summon-the-legen/1100-6456349/

Dragon Ball FighterZ possesses a number of mechanics that aren't as easy to figure out as hurling Ki blasts with characters. Much like the show it's based on, your characters will be able to collect several dragon balls, with the user being granted a single wish from the legendary dragon Shenron. However, the game doesn't quite spell out how exactly to do this, which may confuse some players who suddenly find a dragon ball during a fight.

In the video above, we lay out what you'll have to do to find all the dragon balls and summon the dragon to grant your wish. Essentially a special comeback move, you'll have to string together a set of combos to score a specific number of hits for each orb. However, what makes this particular meta-challenge so tricky is that your player will compete against the opposing player for the dragon balls, who can steal the chance to summon Shenron. Once summoned, you'll be granted a selection of four wishes--which include health regeneration, reviving a downed teammate, restoring full Ki energy, and granting maximum health. While these may seem fairly tame, these wishes can make all the difference in a fight.