what episode does leo decapitate shredder?
 

and is there also a time when they fight shredder on a rooftop in the rain?

That episode was Return to New York Part 3. And they did fight Shredder in the rain on the roof top in Shredder Strikes Part 2.

Wait, does that same shredder come back later? Or are there like different people that take over the role of shredder?

edit:i've actually seen very little of the new series, but the first 8 volumes are on their way to my house in the mail. I watched the first episode on youtube and it was AWESOME!!!!

Yeah he comes back. You'll see why in the episode Secret Orgins part 3.

Shredder Strikes Back Part 1.

No...there was plenty of rain in that ep. But that was when Shredder first returned. He actually went head to head with the guys for the first time in The Shredder Strikes. Where there was also rain.

OOOOOOOOOH DUDE! (or dudette) You are in for some serious kick butt action. I love the 2k3 shredder.

You do realize there's three of them right?

dude.

I recieved the first 3 volumes today, plus 5, 7, 8, and 9 today. I've gone ahead and ordered the first 21 volumes, so I've got 3 of the 5 seasons covered already. I've watched the first six episodes plus most of the bonus stuff. God it is so awesome! I was a fan of the old ninja turtles but this just kicks its ass completely! I saw Shredder the first time and was like "whoa, he's not a Mexican with a bunch of stupid techno weapons?" Also, when Shredder grabbed his claw I was like "here we go." But alas they just tease you. And then when he held the sword of tengen up to the suit I was like "THAT LOOKS BADASS!!!!"

I really like the new Baxter Stockman too. He's not this whiny little twirp. he actually has his own motives, rather than just being shredder's pawn. April O'Neil is a lot cooler too. The whole reporter going after a story bit was kind of annoying in the old toons.

I also LOVE the new look of the foot soldiers. They look new and stylized but the shape of their head and eyes reminds me so much of the footsoldiers from the original live-action movie.

Everything about this show pwns the old one, (they actually use their weapons, and it's action first, humor second) except for one thing: Splinter's voice. I thought the original Splinter had the perfect voice. In this one it sounds too forced, I dunno. But it does bug me.

COWABUNGA!!!!

Just started vol 3 and OMFG!!!! SHREDDER CUT OUT STOCKMAN'S EYE!!!!!

I knew it!!!That is ssssssoooooooooooooooooo rad! I LOVE this show!!!

try not to read many threads here or you'll get a lot of stuff spoiled quickly since the information is so old no one puts it on spoiler tags.
whoa, kind of a racist remark especially when shredder is japanese...

whoa, spoiler man! he hasn't seen them yet!

yeah he's always been japanese, but in the original cartoons he sure looked Hispanic to me. I was glad to see him looking like he should in the new toons. I'm up to the garbageman episode. I'm trying to save it since I don't have volume 4 yet and i wanna wait til it comes in before I continue. But yeah the first 21 volumes are on their way, can't wait.

PS. Who the hell are those three guys' in the floating chairs with the same voice? Shredder has past enemies aside from the turtles? It's so new and interesting. Also, that old suit that they airlifted out of the water.... it reminded me of Krang because it looked like it had a place where you could put the brain in its stomach. I could be onto something here.

PPS. Don't answer, that was just me thinking aloud.

PPPS. Stockman failed again, maybe this time shredder will cut off his hand. :o