What is G-5 in One Piece?

G-5 is a Marine unit with its own base commander and captains operating on Punk Hazard. In the sources, G-5 marines clash with the Straw Hat crew and allies while attempting to escape the laboratory blocks as gates close and gas spreads. Tashigi serves as a captain directing her men to carry the wounded and reach safety, while Vergo appears as the base commander confronting survivors. The unit shows determination to report threats to headquarters despite heavy losses. One marine states, "WE HAVE TO GET OFF THIS ISLAND AND REPORT TO HQ!!!" ch. 680. Another notes, "WE'VE RECEIVED OUR PRECIOUS CAPTAIN-CHAN, SAFE AND SOUND!!!" ch. 679. Tashigi insists, "THERE ARE STILL A NUMBER OF MARINES OUT THERE!!!" ch. 679. These events establish G-5 as an active Marine force navigating the chaos of Punk Hazard's A-Block and B-Block passages alongside pirates.