After waging a personal war on crime for decades, no one, not even Bruce Wayne, could hold together his broken and aged body.
Years ago, after the public revelation of his true identity, Bruce was attacked inside the Batcave by Bane and Two-Face, who crippled him and destroyed Wayne Manor. Battered but undefeated, Bruce discarded his false playboy persona, even his real name, to permanently become who he really was inside: Batman. Now, ensconced in the Batcave, Batman rules Gotham City with an iron first through his Bat-Knights, an army of robot warriors that patrol the city streets.
The new Batsuit is a power armour that allows Batman to engage in aerial and hand-to-hand combat despite his past injuries. The armour is equipped with grappling hooks and can shield Batman from flames. For combat, the armour is armed lasers, sharp blades, and it can allow Batman to fly. Lastly, in addition to enabling him to walk and to move as he once did, the power armour also lends Batman superhuman strength.
During the events of Kingdom Come, Batman's philosophical and moral beliefs come to the fore as a middle, but no less savory, ground between the Superman's new Justice League and Lex Luthor's Mankind Liberation Front. When Superman first invited him to join his new Justice League, he declined because he saw that metahuman policing of the world, would constitute an unjustified totalitarianism that would only breed resentment in normal humans and exacerbate problems. Instead, Batman's personal values insisted that only those with the will to power and the will to use that power deserve to rule. For these ends, Batman conceived of a slow and methodical approach to quell the crises at hand and to govern the world, as he had. However, events moved more quickly than even Batman anticipated and so he formed his own superhero group to fight for his ideals.