Tony Stark:
Hi I'm Tony,
And this ain't a business call.
This Dark Knights gonna fall before night fall.
You better brace yourself Bruce.
I'll sell all your mistakes right to the news.
This caper crusader,
Can't save to save the day
I'm directly messing this detective,
But I can't give him more trouble than his exes.
Bruce I'm just getting started, and start getting groovy.
I'll see you in the Alleyway next to the movies.

Batman:
Alfred open the cave,
This jerks is only friends with robots he made.
I'm gonna slap this drunk,
You rap was just like your movie ending it stunk.
I'm a hero of Gotham, your a clown.
An Iron Man, Get out of town.
I'm a bat and I'm gonna hit stark,
Out of the park.
So Tony get spelt out,
Even Steve Rodgers betrayed you, I wonder how that felt.

Ironman:
I'll snap back faster than Bane,
Analyze my sentences frame be frame.
Go back to Scooby and do your special.
You can't beat me in any sort of level.
Your a coward I'm a cave,
While everyone knows I'm not afraid,
To say my real name.
You better buckle up because your in for a ride.
When I decide to take this battle into the sky.

Batman:
Man are you kidding me this doesn't suffice.
Are you abusive to alcohol or your wife?
And the battle turns like a bat-terang.
It's gonna take more time to defeat me,than time to catch Kang.
Your a joke of a prodigy.
Captain America got more done while frozen in the sea.
Your executed tin man.
I'm leaving. See ya. I'm Batman.

EXPLANATION

Tony Stark:
Hi I'm Tony,
And this ain't a business call. (Both contestants lead big businesses)
This Dark Knights gonna fall before night fall. (Batmans nick name dark night)
You better brace yourself Bruce. (Brace and Bruce is a play on words)
I'll sell all your mistakes right to the news.
This caped crusader, (another batman nickname)
Can't save to save the day
I'm directly messing this detective, (destroying)
But I can't give him more trouble than his exes. (Cat women, black canary problems)
Bruce I'm just getting started, and start getting groovy.
I'll see you in the Alleyway next to the movies. (Where his parents were murderred)

Batman:
Alfred open the cave, (bat cave)
This jerks is only friends with robots he made. (A reference to Jarvis or just an rather very intelligent system)
I'm gonna slap this drunk, (iron man is an alcoholic)
You rap was just like your movie ending it stunk. (A lot do critics don't like the way the iron man series ended)
I'm a hero of Gotham, your a clown. (Joker is a clown Batman fights and usually beats up)
An Iron Man, Get out of town. (Telling Iron man to leave Gotham while telling him
I'm a bat and I'm gonna hit stark,
Out of the park. (A bat hits a ball out of baseball parks)
So Tony get spelt out, (spell it out means explain so batman is explaining iron mans flaws)
Even Steve Rodgers betrayed you, I wonder how that felt. (Cilvil war reference where Captain America deserted iron mans judgement to save his old friend Bucky)

Ironman:
I'll snap back faster than Bane, (Bane broke Batman's back)
Analyze my sentences frame be frame. (Another way of saying listen closely)
Go back to Scooby and do your special. (Batman has teamed up with Scooby-Doo on multiple occasions, so Iron man is accusing Batman of being a role model for only toddlers)
You can't beat me in any sort of level. (Another way of saying he is out of his league)
Your a coward In a cave, (he hides in the bat cave)
While everyone knows I'm not afraid,
To say my real name. (Iron mans name is not closely guarded)
You better buckle up because your in for a ride. (Batman wears an utility belt which is what he is referencing to 1: buckle up stay safe 2: giving him a fair warning)
When I decide to take this battle into the sky. (Ironman can fly)

Batman:
Man are you kidding me this doesn't suffice.
Are you abusive to alcohol or your wife?
And the battle turns like a bat-terang. (A Battarang changes directions much like batman is telling him this raps momentum is)
It's gonna take more time to defeat me,than time to catch Kang. (Kang travels through time and goes through time meaning it takes years for the avengers to catch him)
Your a joke of a prodigy. (Questioning iron mans dignity)
Captain America got more done while frozen in the sea. (He is saying The thought of captain America is more powerful than iron man in action)
Your executed tin man. (The first actor for the Tinman in the wizard of Oz died from his costumes lead poisoning)
I'm leaving. See ya. I'm Batman. (This battle ends with Batman's catch phrase)