Batman, the epitome of human intellect and preparation in the DC Universe, is well known for having a contingency plan for virtually every situation—including taking on his fellow Justice League members, should the need arise. Among his vast arsenal of gadgets and strategic assets, one stands out as particularly versatile: The Hellbat Armor.

The Hellbat Armor was forged by the Justice League themselves, with each member contributing to its creation. Superman charged it in the heart of the sun, enhancing its strength; Cyborg integrated advanced alien technology allowing unparalleled computational capabilities; Wonder Woman infused it with endurance from the Gods; Flash added Speed Force to allow it to move at incredible speeds; Green Lantern wrapped it in willpower-fueled constructs making it nearly indestructible; Aquaman made it adaptable to subaquatic environments, and Batman himself applied his tactical genius into its design.

But what makes the Hellbat truly Batman’s best contingency gadget is its capability to adapt to and counter two Justice League heroes who are wildly different in power and ability: Superman and Aquaman.

Firstly, against Superman—one of the most formidable beings on Earth—the Hellbat’s heat-resistant design enables Batman to withstand Superman’s heat vision. The armor’s servos grant Batman the strength he needs to hold his ground against Superman’s superhuman power. Should Superman go rogue, he would find a worthy adversary in a human encased in an armor capable of trading blows with gods.

On the other hand, dealing with Aquaman showcases an entirely different set of capabilities. The King of Atlantis is a master combatant both above and below water, commanding sea creatures and manipulating water itself. Against Aquaman’s aquatic prowess, Batman can utilize the Hellbat’s subaquatic adaptions provided by Aquaman himself—ironic resilience that could withstand crushing ocean pressures and allow for undersea combat without handicap. The suite’s life support systems prevent drowning while its enhanced sensors can detect any approach, making ambush by sea life or Atlantean forces less effective.

Furthermore, The Hellbat’s ability to elevate Batman’s own physical abilities means he retains hand-to-hand combat prowess against foes like Aquaman or anyone trained in diverse martial arts disciplines.

In conclusion, Batman’s Hellbat Armor is a remarkable piece of engineering, effectively enabling him to battle two completely different superheroes—Superman with cosmic-level strength and Aquaman with mastery over the oceanic domains. These capabilities solidify its standing as Batman’s ultimate contingency plan gadget—not just for these scenarios but as an armament adaptable against a wide array of superhuman threats.