*WARNING: THIS FAQ CONTAINS MAJOR PLOT SPOILERS*
#1 REGULAR ENDING - LESS THAN 100% GAME COMPLETION
Scarecrow tries to use numerous doses of the fear toxin on Bruce Wayne but because the infection of Jokers blood it does not have the desired effect. Instead Bruce is able to use the fear toxin as a way to ris him self of the Joker persona invading his psyche. After he defeats Joker within his mind he is able to escape thanks to the Arkham Knight who shoots him free of his bonds. Batman then takes out Scarecrow by injecting him with his own fear toxin and hands him over to GCPD.
At this point you have technically completed the game and if you collected all 243 Riddler trophies and defeated the green man himself you will be able to initiate the Kightfall Protocol Ending
#2 KNIGHTFALL PROTOCOL ENDING - WITH 100% GAME COMPLETION
GAMER NOTE: All Riddler challenges you've completed in your first play through carry over to the new game+ mode along with all of your unlocked abilities making a 2nd go around at a higher difficulty a lot easier.
In this ending we see Bruce destroy the Bat Signal and return to his mansion where Alfred once again asks if he is certain he wants to go through with it. Soon after, as reporters have gathered to get video footage of the Wayne Estate and Bruce Wayne himself, the mansion explodes. Is Bruce Wayne dead....? muhahahahahaha
Time jumps ahead and we see that Commissioner Gordon has been elected Mayor and Batgirl and Robin are getting hitched, YAY! Gordon's voiceover from the beginning of the game continues where it left off and we are left with a familiar scene, a wealthy family making the poor decision to walk down a dark alleyway after a night out in Gotham. Two men pull out guns but are interrupted by a masked figure perched upon a roof. They taunt the dark figure who then fly's at them like something out of a Batman nightmare. The end.
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