Isaac has a long, beak-like nose, short hair and a dark moustache. He wears a light-colored cape, a light shirt and striped trousers.
He seems to be weak to compliments as he became flustered when Roger spoke highly of the crew.
Abilities and Powers
In his concept art, Isaac wields a sword. He has not been seen using it though.
At some point, Isaac joined the Roger Pirates. On an island in Paradise, the Roger Pirates defeated a battalion of Marines when they spotted the Whitebeard Pirates approaching them. When the Whitebeard Pirates arrived, the two crews battled each other for four days until the fight settled into a gift exchange. Roger pleaded for Whitebeard to allow his subordinate Kozuki Oden to join the Roger Pirates and help them reach the final island.
When Oden and his family boarded the Oro Jackson, the crew initially treated Oden coldly, but they quickly warmed up to him as friends as they sailed to many destinations including Skypiea, Water 7, Fish-Man Island, Wano Country, and Zou. They then made it to the final island and laughed when they saw the treasure left behind by Joy Boy. After departing from the island, named Laugh Tale by Roger, the crew had a party before tearfully bidding farewell to their captain. They then took Oden back to his home in Wano and tearfully said goodbye to him as well. The Roger Pirates disbanded, and it is unknown what became of Isaac.