Internal combustion engine comprising: - an intake manifold which can provide gaseous medium to a plurality of piston-cylinder-units; - at least one cylinder head with the plurality of piston-cylinder-units, each piston-cylinder-unit having at least • a main combustion chamber for combustion of a combustion charge, a volume of the main combustion chamber being defined by the at least one cylinder head and a reciprocally moving piston, • at least one intake valve for coupling the main combustion chamber to the intake manifold, • a prechamber which is coupled to the main combustion chamber and • an ignition device arranged in the prechamber to start combustion of the combustion charge indirectly via flame torches which enter the main combustion chamber from the prechamber and are created by the ignition of an ignitable air-fuel-mixture inside the prechamber; - at least one ammonia source (13, 14) for providing ammonia to each piston-cylinder-unit • via the intake manifold and the at least one intake valve as part of gaseous medium in form of a mixture of at least air and ammonia as part of the combustion charge and • via at least one prechamber valve provided to the prechamber; - at least one hydrogen source for providing hydrogen to the prechamber via the at least one prechamber valve of each piston-cylinder-unit, the at least one hydrogen source comprising at least one reformer for cracking ammonia; and - a control device to operate the internal combustion engine, wherein the control device is configured to at least control an actuator for controlling a ratio of hydrogen to ammonia of hydrogen-enriched ammonia provided to the prechamber. - an intake manifold which can provide gaseous medium to a plurality of piston-cylinder-units; - at least one cylinder head with the plurality of piston-cylinder-units, each piston-cylinder-unit having at least • a main combustion chamber for combustion of a combustion charge, a volume of the main combustion chamber being defined by the at least one cylinder head and a reciprocally moving piston, • at least one intake valve for coupling the main combustion chamber to the intake manifold, • a prechamber which is coupled to the main combustion chamber and • an ignition device arranged in the prechamber to start combustion of the combustion charge indirectly via flame torches which enter the main combustion chamber from the prechamber and are created by the ignition of an ignitable air-fuel-mixture inside the prechamber; • a main combustion chamber for combustion of a combustion charge, a volume of the main combustion chamber being defined by the at least one cylinder head and a reciprocally moving piston, • at least one intake valve for coupling the main combustion chamber to the intake manifold, • a prechamber which is coupled to the main combustion chamber and • an ignition device arranged in the prechamber to start combustion of the combustion charge indirectly via flame torches which enter the main combustion chamber from the prechamber and are created by the ignition of an ignitable air-fuel-mixture inside the prechamber; - at least one ammonia source (13, 14) for providing ammonia to each piston-cylinder-unit • via the intake manifold and the at least one intake valve as part of gaseous medium in form of a mixture of at least air and ammonia as part of the combustion charge and • via at least one prechamber valve provided to the prechamber; • via the intake manifold and the at least one intake valve as part of gaseous medium in form of a mixture of at least air and ammonia as part of the combustion charge and • via at least one prechamber valve provided to the prechamber; - at least one hydrogen source for providing hydrogen to the prechamber via the at least one prechamber valve of each piston-cylinder-unit, the at least one hydrogen source comprising at least one reformer for cracking ammonia; and - a control device to operate the internal combustion engine, wherein the control device is configured to at least control an actuator for controlling a ratio of hydrogen to ammonia of hydrogen-enriched ammonia provided to the prechamber.