A fuel nozzle, comprising a center body and a gas-only cartridge that extends axially within the center body; the center body comprising: a tip body disposed at a downstream end thereof, the tip body defining an opening that extends axially through the tip body and including a plurality of channels circumferentially spaced and positioned along an inner surface of the tip body within the opening, wherein each channel defines a flow passage through an upstream surface and a downstream surface of the tip body, the gas-only cartridge comprising: a flange defining a plurality of apertures for receiving a gaseous fuel; an outer tube coupled to the flange and extending axially outwardly from the flange; an inner tube extending axially within the outer tube, wherein the inner tube and the outer tube define a fuel passage therebetween, wherein the fuel passage is in fluid communication with the plurality of apertures of the flange; wherein the inner tube at least partially defines an air passage within the gas-only cartridge; wherein the outer tube and the center body having an annular or tube shape define a secondary premix air passage therebetween; wherein the flange at least partially defines at least one air circuit, wherein the air circuit is in fluid communication with the air passage; a fuel distribution tip disposed at a downstream end of the gas-only cartridge, the fuel distribution tip defining a plurality of fuel ports circumferentially spaced along and annularly arranged about an outer surface of the fuel distribution tip, wherein the fuel ports are in fluid communication with the fuel passage and one or more of the channels; and wherein the fuel distribution tip defines an aperture disposed along a downstream surface of the fuel distribution tip, wherein the aperture is in fluid communication with the air passage in a way that only compressed air from the air passage exits via the aperture. the center body comprising: a tip body disposed at a downstream end thereof, the tip body defining an opening that extends axially through the tip body and including a plurality of channels circumferentially spaced and positioned along an inner surface of the tip body within the opening, wherein each channel defines a flow passage through an upstream surface and a downstream surface of the tip body, the gas-only cartridge comprising: a flange defining a plurality of apertures for receiving a gaseous fuel; an outer tube coupled to the flange and extending axially outwardly from the flange; an inner tube extending axially within the outer tube, wherein the inner tube and the outer tube define a fuel passage therebetween, wherein the fuel passage is in fluid communication with the plurality of apertures of the flange; wherein the inner tube at least partially defines an air passage within the gas-only cartridge; wherein the outer tube and the center body having an annular or tube shape define a secondary premix air passage therebetween; wherein the flange at least partially defines at least one air circuit, wherein the air circuit is in fluid communication with the air passage; a fuel distribution tip disposed at a downstream end of the gas-only cartridge, the fuel distribution tip defining a plurality of fuel ports circumferentially spaced along and annularly arranged about an outer surface of the fuel distribution tip, wherein the fuel ports are in fluid communication with the fuel passage and one or more of the channels; and wherein the fuel distribution tip defines an aperture disposed along a downstream surface of the fuel distribution tip, wherein the aperture is in fluid communication with the air passage in a way that only compressed air from the air passage exits via the aperture. a flange defining a plurality of apertures for receiving a gaseous fuel; an outer tube coupled to the flange and extending axially outwardly from the flange; an inner tube extending axially within the outer tube, wherein the inner tube and the outer tube define a fuel passage therebetween, wherein the fuel passage is in fluid communication with the plurality of apertures of the flange; wherein the inner tube at least partially defines an air passage within the gas-only cartridge; wherein the outer tube and the center body having an annular or tube shape define a secondary premix air passage therebetween; wherein the flange at least partially defines at least one air circuit, wherein the air circuit is in fluid communication with the air passage; a fuel distribution tip disposed at a downstream end of the gas-only cartridge, the fuel distribution tip defining a plurality of fuel ports circumferentially spaced along and annularly arranged about an outer surface of the fuel distribution tip, wherein the fuel ports are in fluid communication with the fuel passage and one or more of the channels; and wherein the fuel distribution tip defines an aperture disposed along a downstream surface of the fuel distribution tip, wherein the aperture is in fluid communication with the air passage in a way that only compressed air from the air passage exits via the aperture.