Great Gladiator! Trophy
Complete all 21 Arena Challenges
After Chapter 3, Brock will be on the right side of the ship. Talk to him to view the Arena Challenges, you will notice three different arenas, each with 7 challenges. Only the first arena will be unlocked after Chapter 3. The additional arenas unlock after Chapters 7 and 12. Complete all 21 challenges and the trophy will unlock.