Nightwing's Regime costume is Damian Wayne. This makes Nightwing one of several characters to have different people as alternative costumes. Spoiler:It is revealed during the game that the alternate dimension version of Damian killed Dick Grayson, the current true Nightwing, took his mantle and joined Superman's regime.

The other characters with different people as costumes are Green Lantern (with a John Stewart costume) and Superman's Cyborg outfit (which is actually a character named Hank Henshaw.)

When Batman uses his anti-air Bat Claw move he yells "Get down here". This is a reference to another NetherRealm Studios series, Mortal Kombat, inwhich the character Scorpion yells "Get over here!" when he uses his spear move.

When wearing the "Regime" skin, Superman's victory cut-scene has him ordering his foe to "Kneel before me!" This is most likely a reference to the famous line in Superman 2 where General Zod declares "Kneel before Zod!"

In the Arkham Asylum stage, there are many references to the Batman Arkham series. The first is Hugo Strange in the background observing the fighters. He looks exactly like he does in Batman: Arkham City. The second is in the first stage transition (from the Main Hall to the Mess Hall) where the player is attacked by Scarecrow. He too looks like he does in Batman: Arkham Asylum. Finally, during the second stage transition (from the Mess Hall back to the Main Hall) where the player is beat up by Killer Crock, The Penguin, The Riddler & Two Face who also share their appearences from the Batman Arkham series.

Shinnok's Amulet, an item from Mortal Kombat commonly worn by him or Quan Chi, can be found in the museum at the Metropolis Stage.

The Joker, Ares, Black Adam , and Scorpion are the only characters in the game who kill their opponents after they win the fight. The Joker burns his foe, Ares throws swords at him/her, Black Adam severely shocks his opponent, and Scorpion stabs them with his sword and sends his enemies into the Netherealm.

Since the early versions of the game, the Metropolis stage has had a number of changes. The original time of day was daytime, but the weather in the final version is overcast. The TV in the streets had the Regime's logo which faded to Superman with glowing eyes and then back again. The final versions have just the logo. In an earlier version, it shows the Daily Planet logo as unfinished on the rooftops, but in the final versions it's shown completed.

Deathstroke's pose when activating his super-move is based on the cover of New 52 Deathstroke #1.

Aquaman's bio in the Archives incorrectly states that he can fly.

Flash's victory sequence is very similar to one of his "Heroic Brutality" moves from Mortal Kombat vs. DC Universe.

In the Fortress Of Solitude stage, there's an easter egg in which Doomsday (in the background) will have a costume on from the "Death Of Superman" comic, which cannot be used in game. In order to activate this easter egg, both players need to play as Doomsday. One player needs to choose his regime costume, and the other needs to choose his regular costume. The costume was added to the game later as DLC.

Concept art shows John Stewart as the represented Green Lantern, while in the final release, Hal Jordan was used instead. However, John Stewart did make an appearance as a downloadable skin for the Green Lantern after the game's release.

When a stage transition has been performed in the Great Hall area in the Hall of Justice stage, Darkseid makes a cameo appearance.

Batman had his super move completely changed before the release of the game due to lackluster reception from fans. His original move was a parry attack, followed by several blows to the opponent and the use of his batclaw to hang the opponent for a final jump kick.

After Joker defeats Regime Nightwing, he states that there has been a "death in the family." This is a reference to the 1989 comic of the same name.

When playing on The Watchtower level, Martian Manhunter will make an appearance to the far right of the Bridge in the background. However, he won't appear if he is participating in a fight.

Green Arrow has a free downloadable costume based off of his depiction from the 2012 television series "Arrow."

Additionally when clad in this costume, Arrow's voice actor will change to Stephen Amell, his actor from the show.

The reveal trailer for Green Arrow was released the same day as the premiere of "Arrow" on The CW television network.

When Superman's Red Son skin was first revealed, he still used the intro from his default skin. This was changed to the intro for his Blackest Night, Godfall, New 52, Man of Steel and Cyborg Superman skins.

When Cyborg wins a round, he will shout "BOOYAH!", his catchphrase from the Teen Titans animated series.