does anybody know why did riku become a big guy

Yes, DiZ says it in the game.
DiZ told Riku to go capture Roxas. Having Roxas would speed us Sora's awakening (See Kingdom Hearts, Chain of memories). Riku Went to the world that never was, and fought Roxas so that he might bring him back to DiZ. Riku fought hard, but lost. Then he decided that to fight in darkness, he would have to immerse himself in that same darkness, and became Ansem, The Seeker of Darkness, who took over Riku in Kh and Kh Chain of Memories. There you go. If you meant the other form of Riku, well, it has been a year later since Kh

 

He became Ansem so that he could capture Roxas after being beaten by him on a collection mission for DiZ.

 

Don't you know that KH2 begin one year after KH1? I think you must be never played Kingdom Hearts Chain Of Memories and Final Mix+. Play both of them or look at youtube to know the reason.

 

R u talkin 2 me or Crazykh? Also, what r the video's called.

 

Crazykh

YouTube - *VOICES* KH2 Final Mix: Riku Vs. Roxas (English Subs)

The video

 

OK Cool. Thanks XD

 

Sounds good. I'll look it up when i get home. My school has that site blocked.

 

Errmmmm learn to type your words out fully. N00b./

 

Lol, learn not to hold out your Erm you illiterate dog.

 

just because he types like that doesn't mean he is a a noob. I type like dat, n im pretty sure i know 2 times as much about KH and alot of other things, then you.
plus if we are talking about grammar then you spelled N00b incorrectly, there are no 0's in a word, its Noob.
please don't make fun of peoples grammar, maybe thats the way the like to type.

anyway,
To put this easily, Riku fought Roxas, He didn't really LOSE, anytime since they only fought once, what he meant by Lost is that he lost when he wasn't counting on the power of darkness. He considers using the power of darkness losing. Actually, Riku could have won without the power of darkness. but him thinkin, if i fight in the realm of darkness, i might as well be the darkness. By him using this power, He turned into Xehanort's heartless, because he was still inside of his heart(from when he took over riku's body in KH1). But this is a fight that couldn't have happened. Riku just wanted to hurry and wake sora up. Riku confirmed that he never had to fight Roxas, eventually he would have woke up because Roxas left Org 13 to basically find Sora.

 

ENK, WRONG! Would you like to try again?

This is a direct quote from the game...

Ansem talking to Micky in The World That Never Was
"...I can only surmise Riku lost that fight..."

Riku talking to Sora.
"The NEXT time, I made sure I was the stronger one."

They really did fight twice. The first time he fought without darkness, the next time he won with his darkness. He met a victory condition, AND a losing condition.

 

actually you are correct so i stand corrected. so im half wrong sue me? but he didn't really LOSE, he more like gave up, because he could have beat roxas at anytime. If your still going by the game quotes then your way WRONG! im betting you still think Xehanorts heartless, is a heartless no?
but nomura does state that riku thinks of himself as A LOSER(not exact words) for using the power of darkness.

 

But he IS a heartless. Sora and kairi were to. A heartless is a creature who only has a heart. Sora and Kairi were just nice heartless, cause they didn't have their nobodies. Riku lost, you saw it happen in the game. He got his sorry butt handed to him. How he knocked out Roxas, i don't really know. It was two fights. Just back to back.

 

WRONG! would you like to try again? PoH's can't become heartless since they have pure hearts.

Kairi WAS NEVER A HEARTLESS..just an empty shell
SORA WAS a heartless but not for long

A heartless is a being who consumes a heart with darkness, and loses all memories, abilities to speak,and feelings

Xehaort, Nor Sora lost any of those, they were just free roaming hearts, not a heartless.

go read the ansem report 12

 

My bad. It's just the way i see it.
Which one? Normal or secret

 

Sorry. I was in a hurry. Look at all of my other posts and you'll see that I am grammatically correct.

Ouch!

Double Ouch! I didn't say it so don't bring it back to me.

Ummm... Yeah... I think that's it?

Look at the video that Trump posted on page one EVERYONE. That's the actual moment!!!

Ding Ding Ding!!! Correctomundo!!!

 

It was illiterate dude so you'll have to live with it. No need to school me on this stuff. Riku fought twice. He lost 1 and won 1. Thats how it goes. I have examined this from every possible angle, and i have concluded that.

 

OK. Whatever... Just watch the video on page 1. Riku is thrashing Roxas and then Riku thinks that Roxas is defeated then Roxas gets up and swipes at Riku (who doesn't have a weapon) Riku is cut on the stomach and he realises that he is too weak and hurt to fight Roxas without a weapon ( and he really wanted to get it all over with) so he turned into Ansem. He didn't want to become Ansem because you can see that he was ashamed when DiZ came through the portal so he put his hood up so that DiZ couldn't see his face...