Later, Batman saves Green Lantern and Superman points out the hypocrisy.
Superman: Let me get this straight. You save Green Lantern and that's just fine, but I save you and it's some kind of crime against humanity?
Batman: That's essentially it.
Everyone saying that the Flash used to be more positive.
Batman: They look at us like we're lab rats. Flash: Well aren't we? Batman: Y'know, you really were sunnier back in the day...
Superman leaping to his near death, refusing to listen to everyone's insistence that he can no longer fly.
While fighting Locus, Green Lantern uses a constructed hand to poke her in the eyes, Three Stooges-style.
Supergirl is modeled after her Bronze Age incarnation... which means she's no patience for fools and is very snarky.
In Justice League 3001 #3:
Supergirl: I'm confused, Flash. I thought we were going back to the League's headquarters. The Flash: This is our headquarters. Supergirl: In a castle...? Flash: You've got to admit— it's unique.
And in the fifth issue:
Batman: There's another Batman here on Takron-Galtos, Supergirl. And, from what I've learned— he's a dangerous lunatic. Supergirl: So he's just like you. Batman: I'm not some bloodthirsty vigilante. Supergirl: Ah, the benefits of a damaged memory. Batman: What are you saying? Supergirl: I knew you, Bruce... the REAL you... A thousand years ago. Bravest man I ever met. Batman: Thank you. Supergirl: And the craziest. Batman: That's not the way I remember it.
You wouldn't believe how funny Batman and Supergirl's banter may be:
Batman: What do you think you're doing? Supergirl: Saving you...? Batman: I don't need saving! Supergirl: Well, excuse me for trying to help! Batman: You're as bad as your cousin, you know that? Supergirl: No need to insult me! Batman: That was pretty low. Sorry.
In the fifth issue, the Starro envoy has trouble figuring out restrooms...
Starro: Forgive the delay, Guy Gardner. The Starro consciousness is unfamiliar with these units. Guy: It ain't exactly a complex piece of equipment! Starro: This need for constant waste disposal is a serious flaw in your species' biological design structure. Guy: Really? An' havin' a starfish on your face while some obnoxious cosmic jackass uses your body for his own amusement is a good thing?
Ice vouches for Blue Beetle and Booster Gold's competence... well, after a fashion.
Fire: Please! We're going to launch a covert operation with those two idiots? Ice: They're far more capable than they appear. I think. I hope.