Here are the whole lyrics:

Old Godzilla was hopping around
Tokyo City like a big playground,
When suddenly Batman burst from the shade,
And hit Godzilla with a Bat-Grenade.
Godzilla got pissed and began to attack,
But didn't expect to be blocked by Shaq
who proceeded to open up a can of Shaq-Fu
when Aaron Carter came out of the blue,
and he started beating up Shaquille O'Neal
then they both got flattened by the Batmobile,
but before he could make it back to the Bat-Cave,
Abraham Lincoln popped out of his grave
and took an AK-47 out from under his hat
and blew Batman away with a ratatatat,
but he ran out of bullets and he ran away
because Optimus Prime came to save the day!
This is the Ultimate Showdown, of Ultimate Destiny.
Good Guys, Bad Guys, and explosions, as far as the eye can see.
And only one will survive; I wonder who it will be?
This is the Ultimate Showdown, of Ultimate Destiny.
Godzilla took a bite out of Optimus Prime,
like Scruff McGruff took a bite out of crime,
And then Shaq came back covered in a tire track,
but Jackie Chan jumped out and landed on his back.
And Batman was injured, and tryin' to get steady
when Abraham Lincoln came back with a machete,
but suddenly something caught his leg and he tripped;
Indiana Jones took him out with his whip.
Then he saw Godzilla sneaking up from behind,
and he reached for his gun which he just couldn't find;
because Batman stole it and he shot and he missed,
and Jackie Chan deflected it with his fist
And he jumped in the air and he did a somersault,
While Abraham Lincoln tried to polevault
Onto Optimus Prime, but they collided in the air,
Then they both got hit by a Care Bear Stare!
Repeat Chorus
Angels sang out, in immaculate chorus,
as down from the heavens descended Chuck Norris
Who delivered a kick which could shatter bones
into the crotch of Indiana Jones;
who fell over on the ground, writhing in pain,
As Batman changed back into Bruce Wayne.
But Chuck saw through his clever disguise,
and he crushed Batman's head in between his thighs.
Then Gandalf the Grey, and Gandalf the White,
and Monty Python and the Holy Grail's Black Knight,
and Benito Mussolini, and the Blue Meanie,
and Cowboy Curtis, and Jambi the Genie,
RoboCop, the Terminator, Captain Kirk, Darth Vader,
Lo Pan, Superman, every single Power Ranger,
Bill S. Preston, and Theodore Logan,
Spock, The Rock, Doc Ock, and Hulk Hogan
all came out of nowhere lightning fast,
and they kicked Chuck Norris in his cowboy ass.
It was the bloodiest battle the world ever saw,
with civilians looking on in total awe.
The fight raged on for a century,
many lives were claimed, but eventually,
the champion stood, the rest saw their better:
Mr. Rogers in a blood stained sweater.
Repeat Chorus once again

The animation also has examples of:

Affectionate Parody: This, which is definitely NSFW.
Agony of the Feet: Godzilla's reaction to a Bat Grenade.
Cool Vs Awesome: It begins with Batman taking on Godzilla and only grows crazier from there.
Crying Indian: Indy sheds a single tear after Chuck Norris kicks him in the groin; Mr. Rogers sheds one for the dead.
Driven to Suicide: Mr. Rogers, who commits harakiri at the end of the animation, presumably from guilt over being the last survivor.
Eyedscreen: Godzilla getting mad at Optimus Prime.
Eyes Always Shut: Indiana Jones.
Honor Before Reason: Optimus Prime spends more time saving others than defending himself, which ultimately leads to his defeat.
Rated M for Manly: The song.
Shout Out: A whole bunch during the chorus:
- Mario versus Sonic the Hedgehog.
- Santa Claus getting hit by the DeLorean.
- A Jawa using C3PO to beat up R2-D2.
- Samuel L. Jackson getting tackled by snakes.
- Blue Man Tobias.
- Goku riding the Flying Nimbus.
Staring Kid: The little kid with the ice cream cone, looking on "in total awe."
Stealth Pun: Aaron Carter beats up Shaquille O'Neil. That's how he beat Shaq.