Having been a member of the Whitebeard Pirates for at least twenty years, Marco has an extremely high degree of experience with exposure and combat inside the treacherous New World. Ace's deaths at Marineford, Marco took the position of commander of the Whitebeard Pirates, highlighting his level of intelligence and suitability in taking up a commanding position.He appears to be somewhat playful, pretending to be hurt from Admiral Kizaru's attack with obvious sarcasm, though he can also quickly become serious.He tends to end his sentences in "yoi", for example: "arigato-yoi" (thanks yoi) or "mattero-yoi" (wait yoi).Like many catchphrases in the series, it has no actual meaning other than just being a distinct way of talking, i.e. Being a division head of Whitebeard's crew, Marco had a very strong bond with Whitebeard.Later, under Whitebeard's orders, was delegated the task of ensuring that Luffy lived through the battle in Marineford.In the anime they had a short conversation after he saved Luffy from Aokiji, during which Luffy thanked him for saving him while Marco told him not to worry about it.
Marco is generally calm and level-headed in the face of adversity or challenge; the only emotional moments he has shown so far were directly related to Whitebeard's health (after he was stabbed in the torso by his own subordinate Squard and after his death).Marco, along with his crewmates, considered Whitebeard their "father" much in the same way the great pirate considered them his "children".Marco also had a very strong bond with the other commanders as well as the rest of the crew.Later, starting with Opening 13 "One Day", he was given another color scheme.Once again his jacket was recolored in a much brighter purple, his pants were made dark blue, his tattoo blue and his skin a little brighter.He and Ace seemed to have a close friendship, due to him explaining to Ace the bond between Whitebeard and his crew.Marco also trusted Vista enough to protect Luffy from Mihawk.Having heard stories about Luffy from Ace, Marco was among the first people to recognize the Straw Hat captain in the midst of the battle in Marineford, despite not having encountered him prior.While no direct interaction occurred between the two, Marco, took an immediate like to Luffy after the young pirate stopped Crocodile from attacking Whitebeard.Marco seems to appreciate raw talent, even if it comes from someone whom he had never met before (i.e. Because of this, and based on the fact that Luffy intercepted Crocodile's attack on Whitebeard, Marco immediately took a liking to him.Like many other characters, Marco has a distinct speech style.