Ace possesses inferior haki, inferior speed, inferior offensive, and inferior defensive accomplishments. Zoro is far superior to Ace. Based only on his accomplishments thus far (a 50-60% serious Zoro), this is a difficult match for him. Even with these disadvantages, though, he has already proven himself to be a worthy opponent. Zoro is the strongest of the three Urahachi siblings. He is also the most mature and responsible of the group. Unlike his brother who spends most of his time fighting off invaders from another world, Zoro attends school every day where he meets up with his friends. It is there that he learns about the latest events in the world while having fun at the same time. He is very diligent when it comes to his studies and always tries his best to improve himself. When it comes to fightings, Zoro is a force to be reckoned with. He is extremely skilled in using both hands and feet as weapons which makes him a tough opponent to beat even with your limited skills. Also, since he focuses mostly on hand-to-hand combat, he is at an advantage if you don't know how to use a weapon properly. Finally, he has been trained from a young age in martial arts so he is sure to receive training whenever there's a need for reinforcements from the other side.