For this trophy you'll need to participate and win a Tournament.
Tournament Mode, which is found under Free Battle Mode, pits you against and/or human opponents to see who comes out on top. And with this comes many ways to approach it.There are 3 types of Tournament modes available, all depending on what you're up for.
Free Tournament allows you to choose 4 or 8 (including yourself) entrees, and even giving you the liberty of choosing the characters and difficulty settings, unless they're an actual player.
Perpetual Tournament allows the same character selection feature as FT but with special conditions attached. Before a match starts 2 condition wheels will spin and land on conditions that can change any scenario of a match.
Example:
-Condition 1- If you're hit with an Ult. jutsu, you lose automatically.
-Condition 2- Chakra slowly drains
Challenge Tournament allows you to play standard with select ranks and teams.