1. Monarch has too much physical strength for Broly to handle as he was shown to be capable of fighting Superman-Prime who had Qan-cosmic powers, being able to match even Superman-Prime in strength effectively makes him one of the strongest beings in the DC Universe.
2. His invulnerability makes him virtually impervious to all forms of physical damage with the exception of Superman-Prime's blows however in fairness to Monarch, Superman-Prime is one of the physically strongest beings in existence.
3. Monarch possesses Quantum Field Manipulation. It allows him to absorb and manipulate theoretically infinite amounts of energy, the amount of which he can use is only limited by his imagination and will power. Monarch's energy absorption ability is second to none in the DC Universe.
4. He has no need for sustenance e.g food, water or air.
5. Monarch can manipulate and create matter in the same manner he does to energy.
6. Monarch possesses atomic transmutation abilities being able to turn both Maul and Engineer back to their human forms.
7. His energy can be used for the ability of flight and travel at light speeds.