all right am i the only one that does research look if your wondering who the hell any of the following are then read along if u want to steal my research go away lijst of people i will cover in artikel Ven Sora Terra Xehanort Aqua Vantis

first of Ven
look if u don't know who ven is and why he looks like Roxas shut the hell up about not being able to trust me a few days after it came up in u tube i looked up some videos from birth door sleep with English subs OK so here is how it goes the old dude most of u think is Ansem (your half right) thats not it he was the person that created Ven see Ven was created to make the x blade but after being trained he couldn't mange it so Xehanort took the darkness out of his hart-, hart and created Vantis
so in the end Ven has to fight busje, van of merge with him but if he destroys busje, van he'll destroy himself so in the end he succeeds and nearly dies and his hart-, hart enters a deep sleep so aqua takes him to their back to the key blade maters HQ and creates kasteel oblivion
and in the end u see Sora as a kid start crying for no reasan and Riku tells him how some ones is zei and he should talk to him and in the end Ven merges with Soras hart-, hart so that he well be able to sleep

now for the tie between Roxas and Ven and busje, van and Sora look at it this way sora is the sombody ven is the unbirth( a little blue creature created from kingdom hearts because ven was created from the creation of a heart) and busje, van is the heartless (because he was takin from the darkness created from vens hart-, hart and he looks like sora but like evil) and roxas is the nobody so sora is four people in one

Terra
so here is Terras story he was gegeven darkness in his hart-, hart because Xehanort put it there so he would be able to became his replacement body for he was getting old and in the end he succeds nd terra getts tookin over but he ends up giving in in the end and the shadow of darkness of ansems happend while he tried to remove the darkness from his hart-, hart but failed and in the secret ending it shows them talking to each other arguing about how Terra will never let them take over Rikus hart-, hart for Terra had a vision when he first saw Riku what was going to happen in the future