But the teacher changed to Masked on the second day.
Masked explained battlefield first aid.
This had originally been Leo's domain, but Leo had always liked leaving professional matters to professionals, so Masked was given the opportunity to teach on his own.
Leo had not originally known how advanced Masked's medical skills were, but that did not stop him from teaching Masked some simple medical knowledge from his previous life, such as blood vessels and nerves. Combined with the first-aid knowledge Leo had taught, Masked's medical skills advanced by leaps and bounds.
He was a doctor born and raised in the One Piece World. After being exposed to Leo's modern medicine, he improved dramatically.
He had been born into an aristocratic family and received an excellent education. He had once belonged to the propertied class, and yet somehow, a man of means and perseverance had become a penniless pirate.
However, his good education meant that his thinking was clear and his logic sound. Anything Leo explained once, Tarik could fully grasp and develop his own ideas about. His teaching ability was second only to Leo's.
Whenever he taught first aid, none of the pirates dared relax. This was knowledge that could save their lives. After all, not every ship had a ship doctor like those elite Pirate crews.
What they learned now would be the key to saving their own lives in the future.
In fact, the ability of Trafalgar Law, the "Dead Surgeon," was to slice people apart piece by piece without harming them. It was a genuine slicing ability, and it looked terrifying—someone could be cut into several sections and still remain alive.
Yet this was precisely the ability most doctors in this world dreamed of. Their understanding of the human body's structure could only come from corpses.