Although One Piece has tons of training arcs, we don’t talk much about one of its mentors, the head honcho of the Revolutionary Army. Most conversations around how the Straw Hat crew’s strength grew focus on what Rayleigh taught Luffy and what Mihawk showed Zoro. The Revolutionary Army commander who spent 2 years shaping up Sanji should really get some love in these discussions too.The fact that Emporio Ivankov trained and influenced a lot of the cooking skills of Black Leg is often overlooked or not given much attention. Even though Ivankov’s appearance is very flamboyant and the way he trains is non-traditional, he's achieved great success with his methods.The 99 Recipe Trial that took place at Momoiro Island transformed Sanji into someone who could fight on par with the rest of the crew using Haki and techniques that are as advanced as those of his comrades.Sanji's training session (Image Source: Toei Animation)Sanji didn’t go to Momoiro Island on vacation, but instead, Ivankov had created a format for Sanji that pushed him as Black Leg. There was a structure to this Challenge: The 99 Recipe Trial, a challenge where Sanji had to defeat 99 New Kama Kenpo masters to earn the right to use each Cooking Technique. It was way more than just learning to cook, but it gave Sanji an incredible experience.Sanji learned two different styles of Haki through fighting harder opponents over time. Instead of learning how to hit stuff with Haki individually, he did it by fighting real people. There was no theory involved in talking with Ivankov, like there was with Rayleigh for Luffy.Different Training Philosophies in One PieceSanji kicks the laser beam of Kizaru (Image Source: Toei Animation)The One Piece narrative presents various training approaches throughout its story. Rayleigh trained Luffy in Haki forms and how to use them. Mihawk trained Zoro on how to use his swords and fight. These mentor/student relationships are very obvious and should be celebrated.Unlike traditional ways of teaching, Ivankov gave Sanji harder things to deal with, then gave him the option to figure out on his own how to get through it. This type of training is similar to the way most coaches teach. Coaches will assign their players things to do without giving them a ton of directions or how-tos. You learn by doing and experimenting.Sky Walk and Sanji's Combat Evolution in One Piece Luffy and Sanji (Image Source: Toei Animation)Sky Walk shows how Ivankov helped Sanji grow through their training together on the island. Sanji has been forced to get creative with moving because of the constant chases by the inhabitants of the island. Instead of staying on the ground, Sanji has learned to utilize his ability to fly. Sky Walk is similar to CP9's Moon Walk, but is much quicker and more efficient than the Moon Walk.In One Piece, Sky Walk has been one of Sanji's most important parts of his fighting style since the time-skip. Being able to move around in 3-D space gave him a huge advantage when he fought. It's not like Ivankov directly taught him how to do this by showing him, but when you are in a survival situation, out of necessity, you will come up with new ideas.Germa Enhancements and Natural AbilityIn One Piece, Judge's genetic modifications to Sanji made him even more capable than he was before. But when he became "awakened," it didn't take away from Ivankov's contributions as a revolutionary commander and the foundation Sanji had to build on his own to be able to tap into those powers.During his training on Momoiro Island, Sanji was able to build both his physical and mental capacity to help him deal with the potential for genetic modification from Germa genetics. Before training with Ivankov, training had not prepared him for the appearance of the genetic modifications; as a result, he would have been unable to control or manage his abilities when they manifested.ConclusionEmporio Ivankov really progressed Sanji in One Piece by letting him learn hands-on. By putting Sanji through realistic struggles, tough battles, and unique experiences, he helped Sanji grow as a strong fighter. What Sanji has accomplished after the time skip is entirely because of the work he put in with Ivankov during those 2 years on Momoiro Island.Recognizing Ivankov's contribution doesn't require diminishing other mentors. It simply means giving credit where credit is due. In my opinion, all types of training and development should be celebrated by the community, since they are all relevant to the One Piece franchise. The way Sanji grew under Ivankov's mentorship is another way to get strong.