Who is terra?

Answer 1

he is an optinal super-mega-hard boss in kingdom hearts 2-final mix.

That is true but he is actually... ONE OF THE 6 KEYBLADE MASTERS, BEFORE SORA, RIKU, ROXAS, XION, AND KAIRI. THE SIX IN BIRTH BY SLEEP, WHICH IS NOT KH3, IS THEIR STORY. VEN, AQUA, AND TERRA ARE THE ONE'S WHO FIGHT MASTER XEHANORT, HE CAN USE THE KEYBLADE, AS WELL AS HIS GUARDIAN, AND MICKEY. The game he is in is BIRTH BY SLEEP and it is A 10 YEAR PRELUDE TO KH1.

Terra may also have taken master xehanorts name when he defeted him and then go on the ansems apprentice as stated in KH 1 & 2 and gone on to steel ansems name and create ORGANIZATION 13 and after this his heart was eaten by darkness and his nobody was created aka Xemnas.

the point that backs this up is in the birth by sleep trailor he looks up and his eyes turn from blue to a creepy yellow like xehanorts, (fake) ansems and Xemnas.

making him in fact Xemnas

or.. SHE could be someone on Teen Titans that bb falls in love with she thinks he lied so she goes to Slade. then she goes back betrays them cheges her mind stops taking over the city and turns her self to stone in the posses. then she somehow is a school girl who is normal before she could control the earth now bb has to understand "things change"
-Slight Spoiler-

Sora's father is never mentioned or explained in any Kingdom Hearts title to date. Terra meets Sora and Riku for the first time at Destiny Islands, so it is impossible for Terra to be Sora's father.

Answer 2

Terra was a keyblade weilder, like Sora. But because he lost his body to Master Xehanort, his soul lingers in his battle damaged armor (hence the name Lingering Sentiment). He attacks Sora, thinking he is Xehanort, but after he is defeated, he returns to his original pose. He remains there until you challenge him once again, only giving his hatred to Master Xehanort.