- The Comic:
- When Trigon shows up in Year Three, Harley gets excited because she thinks it's "the guy from Legend".
- When Billy Batson is asking random civilians what they think about the heroes more extreme actions, two punk-goth people say that what Superman did to Joker was awesome and hardcore, and say they heard he ripped the Joker's still-beating heart out of his chest. The guy of the pair then yells "Fatality!".
- Harley again, when trapped in Tartarus in Year Four:
- When Detective Chimp appears in issue #10 of Year Four, he's wearing a t-shirt that says "Talking Raccoon? Bitch Please".
- In Year Five #13, Damian and Alfred talk about why each of them joined the side they did. Eventually, Alfred asks Damian if he really came all the way to the Batcave to "argue about Batman versus Superman."
- The black uniforms and helmet-masks of the Regime troops are closely similar to the soldiers of a renegade splinter faction army. And what's shown of them in action, they appear equally as effective.
- The Video Game:
- Batman says "Get down here!" while using his grapple move against an airborne opponent.
- Shazam's animation after depleting his opponent's first health bar has him turn into Billy Batson and then back into Shazam. This is almost identical to Shang Tsung's animation for doing the same in Mortal Kombat 9, in which he will turn into his opponent and back into himself. Even the pose is practically the same.
- S.T.A.R. Labs mission titles include:
- Lex Luthor Mission 93: "There and Back Again"
- Green Lantern Mission 115: "None Shall Pass"
- One of the player icons is a Jokerfied version of the Trollface.
- A strip club in the Gotham stage is called Sin Kitty, a reference to Frank Miller's Sin City.
- The Comic:
- In Issue #16, Luke's house has a picture
◊ of Potato Jesus hanging on the wall. - From the annual issue: Steve Trevor is revealed to be a Nazi spy all along in this Earth. Now does this sound familiar to another American soldier named Steve from a rival company whom Trevor is often compared to and had the same happen to him?
- Issue #51 has Athanasia pointing one of her pistols at Ace.
- In Issue #16, Luke's house has a picture
- The Video Game:
- Ghostbusters:
- In his pre-fight introduction with Darkseid, Brainiac asks him if he's a god. Naturally, Darkseid says yes.
- One of Red Hood's responses to the Joker is, "I ain't afraid of no ghost!"
- Harley's chapter is titled The Girl Who Laughs. Also, in said chapter, she tells the Swamp Thing: "You are amazing!", referencing the Swamp Thing animated series' opening theme song.
- Aquaman and Black Adam's chapter is titled Three Kings, which refers to the monarch duo plus Grodd who gives the Title Drop.
- In their pre-fight introduction, Harley asks Mr. Freeze if he'll make her a pony, Freeze says he'll make the "twilight sparkle". Harley is happy to hear that.
- One of Red Hood's mid-fight one-liners is a reference to You Only Live Twice.
- In one of their pre-fight introductions, Captain Cold states his heart is frozen. Flash responds with "Let it go." He also says this to Mr. Freeze.
- Catwoman's override code for Brother Eye is "LK-4D4." This is Cyrax's identification code in the Mortal Kombat series after his cybernetic conversion.
- In the Gotham stage (outside area), if you kick your opponent into the cinema sign three times, the letters of the movie title will fall away until the sign reads "FINISH HIM"
- The Wizard of Oz is referenced a couple of times in character intros:
- Firestorm says to Scarecrow, "How about a little fire, Scarecrow?", which Scarecrow recognizes as a quote from the film. One of Firestorm's possible responses is "I'll send you over the rainbow," a reference to the film's theme song.
- Cyborg calls Poison Ivy "Wicked Witch of the Green" and she in turn calls him "Tin Man".
- Harley also calls Cyborg "Tin Man", following it up with "Have you no heart?"
- A Harley Quinn & Poison Ivy clash has them quoting the "I love you / I know" scene from The Empire Strikes Back.
- After defeating Bane in Gorilla City, Green Arrow has this to say regarding Gorilla Grodd:Green Arrow: Now where's that damn dirty ape?
- One of Gorilla Grodd's clash quotes is this self-aware one-liner:Gorilla Grodd: You damn dirty human!
- One of Cyborg's clash quotes has him saying that it's time for Play of the Game.
- One of Deadshot's opening interactions against himself goes a little something like this:Deadshot 1: Only one of us is the best shot.
Deadshot 2: Go ahead and hit me with it.
Deadshot 1: Fire away. - A pre-fight interaction between Superman and Captain Cold almost directly quotes Kung Fury:Superman: You got a permit for that gun?
Captain Cold: I got your permit right here.
Superman: Somebody should teach you some manners... - Batman's "Gotham's Hunter (Alternate)" shader is patterned after Boba Fett. Likewise, Cyborg's "Man and Machine" shader represents Samus.
- A possible quote from Doctor Fate is "Shadow of Khemri", referencing the Egyptian-themed Tomb Kings faction from Warhammer.
- The Achievement for beating Story Mode is "Who's Next?"
- A possible line from Braniac when facing off against Batman references the Watchmen comic:Brainiac: You are Earth's greatest detective?
Batman: So it's been said.
Brainiac: The smartest ant is still an ant.- Similarly, some of Superman's intro exchanges with Firestorm have him claim that he's stood on the sun, much like Doctor Manhattan.
- One of Deadshot's mid-fight quotes is "Don't forget, I'm a bad guy".
- If Catwoman's chosen to face off against Grid, she takes a moment to assure Cyborg that she'll "handle Mr. Robot".
- In a match between Brainiac and Power Girl, he calls her Kara Zor-El which she replies "Your princess is in another castle, Brainiac".
- One intro between Batman and Ivy involves the former asking how she escaped, with the latter replying that "life finds a way".
- Several of John Stewart's intro dialogues have him describe his power ring with the sentence "There are many like it, but this one is mine."
- Once of Enchantress's clash quotes is "June can't come to the phone right now."
- In one of the lines from Harley in a clash against Black Lightning, she says "I'm a doctor, not a fortune teller!"
- Catwoman's super move has her backflip off a motorcycle which drops onto her opponent and explodes, a reference to Trinity doing the same in The Matrix Reloaded.
- After Michealangelo wins, he'll tell the pizza to "Get over here."
- After winning a round, one of Ivy's quotes is "So many to kill, so little time."
- One of the Multiverse's awards Epic gear for Robin. The reason? An alternate Damian Wayne thinks he can grow stronger by killing off his multiversal counterparts, and you need to stop him.
- One of Scarecrow's in-game events in Multiverse mode is called "Welcome To My Nighmare"
- One Easter Egg hidden in plain sight includes a yellow name tag on Scarecrow's model used for his regular form (used in his intro for example), which if you look closely at the model, you can see that it says "The Doctor, here to help" a reference to the Doctor Who episode "Closing Time".
- Ghostbusters:
Injustice vs. Masters of the Universe
- Among the threats that Superman considers above He-Man he lists Captain Carrot.
- He-Man saving a woman from a suicide attempt before telling her that she’s stronger than she knows and to keep living is very similar to the iconic scene from All-Star Superman where he saved a young teenager from a suicide attempt.
