THEY KEPT THE ORIGINAL SCENARIO HELL YES!!!
Okay, so in the Anime Style interview for episode 18, Ootsuka and Imaishi talked about how episode 18's script was changed the most out of the entire 3rd arc. Originally, after the Mugan fragments were shot down, the moon would start shooting beams too. Gurren Lagann somehow stops the beams, and is dealt a great deal of damage in return. Then when Simon returns to the surface, the populace would be angry....it would end in a way that builds up more frustration. But they decided to cut this due to time constraints, to make the story more compact, to focus the episode on dialgoue, etc.
BUT THE NOVEL VERSION KEPT IT. :O AWESOME. Simon actually defeated the Mugan and destroyed the fragments all on his own. ("Giga Drill Break Full Drillize!!") And right after, he tried flying straight up to the moon to stop it from falling. But then the moon shot a huge beam at him, and it would destroy the city if he dodged, so he used Gurren Lagann's Giga Drill as a shield, which causes tons of damage to Gurren Lagann. Eventually he has to throw the beam towards some mountains, the Spiral Gage friggin bursts into flame, and Gurren Lagann falls out of the sky. Holy crap. O_O
And then when Rossiu comes to pick him up, Simon is relieved, thinking of him as an "irreplaceable friend," that they'll be able to work this out together, and as a thankful gesture, reaches out to shake his hand. And Rossiu handcuffs him. ;___; DAMMIT THIS MADE ME WANT TO CRY.
Oh oh also, the part where Simon is caught in the middle of the mob. SUCH A GOOD SCENE. With all the people grabbing at him and blaming him and cursing him and calling him the enemy, and Simon doesn't know what the hell is going on and no one is listening to what he has to say, and he could feel some kind of energy boiling inside him, building up like a spiralling drill, until suddenly WHOOSH. Spiral Power. Everyone becomes scared, thinking he's attacking him, and Simon still doesn't get what's going on. Then once he's back in Gurren Lagann he finally realizes that it was the same power that he saw Lord Genome use when they fought seven years ago.
All that, and the fact that I was listening to the OST at the same time, made for some pretty exciting reading. It's a shame that they couldn't keep this stuff in the anime too. o_o
I like that Simon discovers how to use Spiral Power completely by accident (as usual). Like they knew that when humans piloted the Ganmen, there was some kind of energy other than electricity powering them, and that's why they were able to win against the beastmen, but still for all those years they had no clue what it was exactly. But now it's all been revealed. OH SHIT SPIRAL POWER IS THE CAUSE OF EVERYTHING.
EDIT: Coincidentally, my friend Alex just started watching the 3rd arc tonight.
Alex: OMG, ROSSIOU'S LIKE, EVIL!!!
Alex: AND NIA'S A ROBOT!
Alex: SHIT, SON!
Me: not a robot technically, but...yeah
Alex: WELL, SHIT SON!
Alex: Glad Boota's still there.
Alex: but damn, those humans can build shit fast!
Me: yeah, really. it's frightening how quickly civilization developed in seven years... though actually I'm reading the novel version of that story arc right now, and it seems that they found a giant computer underneath Lord Genome's HQ that spit out a ton of information and technology at them. so, that's one reason.
Alex: cause before, they lived in holes.
Me: yeah. it's like, seven years ago they couldn't even read, and now they're sending a rocket to the moon.
Me: and they got their hands on the stuff Lord Genome used for cloning the beastmen too, so...
Alex: SHIT IT'S HIS HEAD IN A BOX!
EDIT 2: "...Aniki!" Simon moaned. "Why, why even Aniki..." DAMMIT. DAMMIT. ;___;