I was just wondering does sephiroth at the end of FFVII still believe he is the last surviving ancient. Me asking this comes from a part during the game where the story reveals that when sephiroth fell into the lifestream and merged with jenova, he gained the knowledge of the ancients. Does this imply that he discovered what jenova really is. Also he says later that he is greater than the ancients in the game. If this is true then his whole reason for wanting to take back the planet from the humans in the name of the ancients is meaningless. His whole reason for doing what he did was because he thought he was the last ancient and the human race stole the planet from his ancestors and his mother. If he knows what jenova really is then why the hell does he still go through with his whole genocide anyway? Any thoughts?
[SPOILERS]Sephiroth's motives?
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Phraquards
(C)loud (S)trife
hello im with you sephiroths motives what the hell re the i got lost after cloud flyed up and gave him the black magic?
DarkClaymore
Fatal Noob
I never really fully understood Sephiroth's motives... I guess that pretty much ruined the plot for me, as it mainly centers around him.
I just don't get it... He could kill off the whole party so many times, and yet he didn't.
He maybe was insane and all, but he was sane enough to understand that Aerith stands in his way. So couldn't he see that the rest of the party is even a greater threat? Morever that Cloud already beat him once in the past.
I thought that he wanted to be killed or something, but that probably isn't right.
Though, I have always believed he'll become good at the end or something (even though I saw AC before playing the game). I thought that MAYBE he dispites what he is (a monster, or at least that what he called others that were created like him, before finding out he is one of them) and wanted Cloud to finish him off.
As well as he saw that Cloud, his own clone (or whatever it is), is accepted by other people and probably thought it is strange. So MAYBE he wanted to test this "strange" relationship Cloud has with his friends and did many things to hurt them.
In the end, realizing that Cloud has something he doesn't, he finally gives Cloud the chance to kill him.
But it is quite baseless. Even though if it is somehow close to the truth, Sephiroth may become one of my most favorite characters. Maybe even the most favorite.
Putting that aside, I am not really sure he did anything for the Ancients or the like.
I think he just wanted power or something (assuming that what I said above is a complete bullshit)
I just don't get it... He could kill off the whole party so many times, and yet he didn't.
He maybe was insane and all, but he was sane enough to understand that Aerith stands in his way. So couldn't he see that the rest of the party is even a greater threat? Morever that Cloud already beat him once in the past.
I thought that he wanted to be killed or something, but that probably isn't right.
Though, I have always believed he'll become good at the end or something (even though I saw AC before playing the game). I thought that MAYBE he dispites what he is (a monster, or at least that what he called others that were created like him, before finding out he is one of them) and wanted Cloud to finish him off.
As well as he saw that Cloud, his own clone (or whatever it is), is accepted by other people and probably thought it is strange. So MAYBE he wanted to test this "strange" relationship Cloud has with his friends and did many things to hurt them.
In the end, realizing that Cloud has something he doesn't, he finally gives Cloud the chance to kill him.
But it is quite baseless. Even though if it is somehow close to the truth, Sephiroth may become one of my most favorite characters. Maybe even the most favorite.
Putting that aside, I am not really sure he did anything for the Ancients or the like.
I think he just wanted power or something (assuming that what I said above is a complete bullshit)
HighwindPilot
White Mage
MASSIVE #%$$&^# SPOILERS, PROCEED AT YOUR OWN RISK:
Before I go into it, I apologize if I have anything jumbled around, but I'll do my best to keep things in a consistent flow.
I guess with Cloud's backstory in Kalm: One of the most important things to note within this backstory is that the Shinra records Sephiroth read about Jenova were innacurate. This was unknown to Sephiroth however, who believed that the Cetra were betrayed and sacrificed by humans, and that his "mother", Jenova, was one of the last surviving members of Cetra before she "died". It was at this time that Sephiroth left Nibelheim to ruins and went to free Jenova from her containment, so that they may find The Promise Land and rule the planet. It was only here, 5 years prior to the events of FF7, that The Promise Land was his goal.
When Cloud struck him down, he made his way to the Lifestream. The Lifestream, as noted in the game, contains the souls (knowledge, emotions, and memories) of those who once lived on the planet. While Sephiroth drifted in the Lifestream, he learned from the Cetra. He learned that he wasn't one of them, that Jenova was actually the very thing that fell from the sky and killed off the race, that the crater Jenova created caused the planet to gather mako/lifestream energy to heal the massive wound (these are all things that the player can learn from Gast's studies with Ifalna at their old house). In addition to this, Sephiroth also learned of "The Black Materia", which could summon the destructive power of Meteor. He learned all he could from the Cetra, before crystalizing himself in the crater that Jenova once created, with a new goal in mind:
Sephiroth's goal in FF7: *Find the Black Materia so that he may use its powers to summon Meteor. Meteor would strike the Earth, creating a wound so immense that the planet would need to call upon strenuous amounts of its Lifestream to heal itself. During this time, Sephiroth would place himself at the center of this wound, so that he could merge with the Lifestream and control it, becoming the "God" of the planet. That part of his goal remained in tact - to rule the planet.
* All this is explained by Sephiroth to the party at the Temple of the Ancients. His exact words, if you'd like, are:
"Mother, it's almost time... Soon, we will become one". Aeris asks how he intends to do this. He replies, "It's simple. Once the planet is hurt, it gathers Spiritual energy to heal itself. The amount of energy gathered depends on the size of the injury. What would happen if there was an injury that threatened the very life of the planet? Think of how much energy would be gathered! Ha ha ha, and at the center of that injury, will be me. All the boundless energy will be mine. By merging with all the energy of the Planet, I will become a new life form, a new existence. Melding with the planet... I will cease to exist as I am now. Only to be rebourn as a "God" to rule over every soul." He goes on to reference Meteor, which is supposed to cause it.
--
So at some point, early in 2007 (5 years after the flashback, when FF7 takes place), Sephiroth set off, using Jenova and Hojo's created "clones" to do his bidding. Sephiroth had some kind of influence over Jenova, and still believed her to be his mother. The clones meanwhile, were really just people that were exposed to mako and injected with Jenova Cells like Sephiroth once was - so they were willed to him due to the cellular connection.
The problem for Sephiroth throughout most of the game was that he needed to learn more about the Black Materia, and where it was in particular. So Jenova, acting (in part, I think) under Sephiroth's will, morphed to take on Sephiroth's appearance, broke out of the Shinra mansion and began searching for the Black Materia with the clones. That's why Dio first mentions to you way back at Gold Saucer that there was a "black cloaked figure of about Cloud's age" asking about The Black Materia.
So that's actually what Sephiroth was after throughout the game. The reason why some end up confused is because, up until the Temple of Ancients, the party and Shinra (sans, MAYBE Hojo) don't know what Sephiroth went through or learned, and we ARE the party. The last thing that any of them remembered, was that Sephiroth mentioned that he wished to seek The Promise Land, so they were under false pretenses that this was his goal. If you notice, throughout most of FF7, the party is confused about things, and usually tend to piece them together as they go along:
- Initially, everyone decides to pursue Sephiroth, because they know it would mean horrid things if he reached The Promise Land. Also, Cloud and Tifa wanted personal revenge for Nibelheim.
- It was later that they learned of The Temple, and Black Materia, and Sephiroth's real goal.
- And proceeding Aeris' death, they followed him North to Jenova's crater, where the he retrieved the Black Materia
- From there, it's simple, they needed to stop him to stop Meteor.
So things unravel the deeper into the game you reach. One of the things I love about FF7 is that we don't magically know everything about everything from the start, as we take on the perspectives of the party. The backlash is that you may have to piece some things together (but it can ALL be learned in the game), so I can understand some degree of confusion. That being said, he clearly states his goal in the Temple.
Before I go into it, I apologize if I have anything jumbled around, but I'll do my best to keep things in a consistent flow.
I guess with Cloud's backstory in Kalm: One of the most important things to note within this backstory is that the Shinra records Sephiroth read about Jenova were innacurate. This was unknown to Sephiroth however, who believed that the Cetra were betrayed and sacrificed by humans, and that his "mother", Jenova, was one of the last surviving members of Cetra before she "died". It was at this time that Sephiroth left Nibelheim to ruins and went to free Jenova from her containment, so that they may find The Promise Land and rule the planet. It was only here, 5 years prior to the events of FF7, that The Promise Land was his goal.
When Cloud struck him down, he made his way to the Lifestream. The Lifestream, as noted in the game, contains the souls (knowledge, emotions, and memories) of those who once lived on the planet. While Sephiroth drifted in the Lifestream, he learned from the Cetra. He learned that he wasn't one of them, that Jenova was actually the very thing that fell from the sky and killed off the race, that the crater Jenova created caused the planet to gather mako/lifestream energy to heal the massive wound (these are all things that the player can learn from Gast's studies with Ifalna at their old house). In addition to this, Sephiroth also learned of "The Black Materia", which could summon the destructive power of Meteor. He learned all he could from the Cetra, before crystalizing himself in the crater that Jenova once created, with a new goal in mind:
Sephiroth's goal in FF7: *Find the Black Materia so that he may use its powers to summon Meteor. Meteor would strike the Earth, creating a wound so immense that the planet would need to call upon strenuous amounts of its Lifestream to heal itself. During this time, Sephiroth would place himself at the center of this wound, so that he could merge with the Lifestream and control it, becoming the "God" of the planet. That part of his goal remained in tact - to rule the planet.
* All this is explained by Sephiroth to the party at the Temple of the Ancients. His exact words, if you'd like, are:
"Mother, it's almost time... Soon, we will become one". Aeris asks how he intends to do this. He replies, "It's simple. Once the planet is hurt, it gathers Spiritual energy to heal itself. The amount of energy gathered depends on the size of the injury. What would happen if there was an injury that threatened the very life of the planet? Think of how much energy would be gathered! Ha ha ha, and at the center of that injury, will be me. All the boundless energy will be mine. By merging with all the energy of the Planet, I will become a new life form, a new existence. Melding with the planet... I will cease to exist as I am now. Only to be rebourn as a "God" to rule over every soul." He goes on to reference Meteor, which is supposed to cause it.
--
So at some point, early in 2007 (5 years after the flashback, when FF7 takes place), Sephiroth set off, using Jenova and Hojo's created "clones" to do his bidding. Sephiroth had some kind of influence over Jenova, and still believed her to be his mother. The clones meanwhile, were really just people that were exposed to mako and injected with Jenova Cells like Sephiroth once was - so they were willed to him due to the cellular connection.
The problem for Sephiroth throughout most of the game was that he needed to learn more about the Black Materia, and where it was in particular. So Jenova, acting (in part, I think) under Sephiroth's will, morphed to take on Sephiroth's appearance, broke out of the Shinra mansion and began searching for the Black Materia with the clones. That's why Dio first mentions to you way back at Gold Saucer that there was a "black cloaked figure of about Cloud's age" asking about The Black Materia.
So that's actually what Sephiroth was after throughout the game. The reason why some end up confused is because, up until the Temple of Ancients, the party and Shinra (sans, MAYBE Hojo) don't know what Sephiroth went through or learned, and we ARE the party. The last thing that any of them remembered, was that Sephiroth mentioned that he wished to seek The Promise Land, so they were under false pretenses that this was his goal. If you notice, throughout most of FF7, the party is confused about things, and usually tend to piece them together as they go along:
- Initially, everyone decides to pursue Sephiroth, because they know it would mean horrid things if he reached The Promise Land. Also, Cloud and Tifa wanted personal revenge for Nibelheim.
- It was later that they learned of The Temple, and Black Materia, and Sephiroth's real goal.
- And proceeding Aeris' death, they followed him North to Jenova's crater, where the he retrieved the Black Materia
- From there, it's simple, they needed to stop him to stop Meteor.
So things unravel the deeper into the game you reach. One of the things I love about FF7 is that we don't magically know everything about everything from the start, as we take on the perspectives of the party. The backlash is that you may have to piece some things together (but it can ALL be learned in the game), so I can understand some degree of confusion. That being said, he clearly states his goal in the Temple.
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DarkClaymore
Fatal Noob
The reason I found it confusing is because he clearly stated his goal.
I just can't understand what he was thinking, revealing his plans to the enemy like that.
I just can't leave the idea he had a different goal. One which he kept as a secret.
So for me, Sephiroth is still a confusing dude. Though at least I now understand a few things better, so thanks for the explanation HighwindPilot.
Maybe I'll learn more if I'll play the spin-offs, but not sure if I'll be able to get them.
I just can't understand what he was thinking, revealing his plans to the enemy like that.
I just can't leave the idea he had a different goal. One which he kept as a secret.
So for me, Sephiroth is still a confusing dude. Though at least I now understand a few things better, so thanks for the explanation HighwindPilot.
Maybe I'll learn more if I'll play the spin-offs, but not sure if I'll be able to get them.
HighwindPilot
White Mage
Everything I mentioned above can be learned from the games. The spin offs might provide you with certain in depth explanations/experiences, but it all equates to the same things you can learn from the original FF7 game.
And it sounds like you're trying too hard/reading too far into things. Sephiroth, ever since confusing himself for a Cetra, had a Messiah complex. What happened after he learned the knowledge of the Cetra in the lifestream? He thought he was even better than the Cetra. When he was at the temple, he knew all odds were in his favor. Because they would either leave the BM for one of his clones to retrieve, or he could control Cloud the way he did. So why hold anything back? His arrogance shined through. Even the manner in which he spoke, was as though he were schooling them on something, "What would happen if you make a wound so deep, that it threatens the very life of the planet?", etc... That's why he told them. The same reason why he killed Aeris, and immediately after, he started about how she would become one with the lifestream and one with him. I mean, he called Cloud a puppet, after all, so I imagine he thought he was unstoppable.
Even then, it's not like he/Jenova weren't inconspicuous about things like the Reunion, so the party didn't even know that was Jenova standing before them, or that Sephiroth actually had yet to GET the BM. He didn't confess everything. It sounds like you're just over-complicating it all.
----
And as for your whole bit above about why he never killed any of them:
For starters, this theory that he even could doesn't quite hold up. Technically, Jenova's attempted to kill them every time she fought the party. And that's who you're fending off for each of those encounters. If you die in battle, then you have been killed, game over, end of story. Aeris however, was vulnerable, in prayer, attempting to save the planet. She didn't even see Sephiroth coming, didn't move, or anything. He caught her while she was in concentration, somewhat alone, and off guard.
But let's say, for argument's sake, that Jenova could have somehow killed you at any given moment. Well let's think: Cloud had the cells of Jenova/Sephiroth inside of him, because of those cells, he was drawn to Jenova in the first place. She had the reunion to look forward to, in which any dismembered part of her would make its way there, including the cells which rested within Cloud. These very same cells, in addition to Cloud's confusion about his past, are what allowed Sephiroth to have LIMITED control over him. We saw, when Sephiroth tried to get him to kill Aeris, that Cloud mentally overcame Sephiroth's will. That's why he started making up lies to Cloud about being a puppet, having been created, never actually existing, etc... So that Cloud would be mentally broken down to serve him. With this kind of control over Cloud, he knew that he could use him as a pond if need be (twice with the BM). These are probably the same reasons that Jenova broke them out of their cells in the Shinra building to begin with.
But would Cloud have been able to make it alone? Doubtful. So why not keep his friends alive? If he doesn't see any of them as a big enough threat, but realizes that they can assist Cloud on his journey, why kill any of them off? Aeris especially had reason to stay alive. She was a Cetra, and had more knowledge of things than even Sephiroth did. If anything, he would keep her alive until he got what he wanted. Once he saw that she was threatening that very thing is when he decided to kill her.
And no, in actuality, they weren't bigger threats than Aeris. What Aeris did was actually summoning the VERY thing that could stop Meteor. A direct counter to his final blow. The party obviously had to struggle with a lot more things to finally reach the point of stopping them. She was much more threatening.
But again, this is all assuming that he/Jenova could kill them at any time - which I doubt.
And it sounds like you're trying too hard/reading too far into things. Sephiroth, ever since confusing himself for a Cetra, had a Messiah complex. What happened after he learned the knowledge of the Cetra in the lifestream? He thought he was even better than the Cetra. When he was at the temple, he knew all odds were in his favor. Because they would either leave the BM for one of his clones to retrieve, or he could control Cloud the way he did. So why hold anything back? His arrogance shined through. Even the manner in which he spoke, was as though he were schooling them on something, "What would happen if you make a wound so deep, that it threatens the very life of the planet?", etc... That's why he told them. The same reason why he killed Aeris, and immediately after, he started about how she would become one with the lifestream and one with him. I mean, he called Cloud a puppet, after all, so I imagine he thought he was unstoppable.
Even then, it's not like he/Jenova weren't inconspicuous about things like the Reunion, so the party didn't even know that was Jenova standing before them, or that Sephiroth actually had yet to GET the BM. He didn't confess everything. It sounds like you're just over-complicating it all.
----
And as for your whole bit above about why he never killed any of them:
For starters, this theory that he even could doesn't quite hold up. Technically, Jenova's attempted to kill them every time she fought the party. And that's who you're fending off for each of those encounters. If you die in battle, then you have been killed, game over, end of story. Aeris however, was vulnerable, in prayer, attempting to save the planet. She didn't even see Sephiroth coming, didn't move, or anything. He caught her while she was in concentration, somewhat alone, and off guard.
But let's say, for argument's sake, that Jenova could have somehow killed you at any given moment. Well let's think: Cloud had the cells of Jenova/Sephiroth inside of him, because of those cells, he was drawn to Jenova in the first place. She had the reunion to look forward to, in which any dismembered part of her would make its way there, including the cells which rested within Cloud. These very same cells, in addition to Cloud's confusion about his past, are what allowed Sephiroth to have LIMITED control over him. We saw, when Sephiroth tried to get him to kill Aeris, that Cloud mentally overcame Sephiroth's will. That's why he started making up lies to Cloud about being a puppet, having been created, never actually existing, etc... So that Cloud would be mentally broken down to serve him. With this kind of control over Cloud, he knew that he could use him as a pond if need be (twice with the BM). These are probably the same reasons that Jenova broke them out of their cells in the Shinra building to begin with.
But would Cloud have been able to make it alone? Doubtful. So why not keep his friends alive? If he doesn't see any of them as a big enough threat, but realizes that they can assist Cloud on his journey, why kill any of them off? Aeris especially had reason to stay alive. She was a Cetra, and had more knowledge of things than even Sephiroth did. If anything, he would keep her alive until he got what he wanted. Once he saw that she was threatening that very thing is when he decided to kill her.
And no, in actuality, they weren't bigger threats than Aeris. What Aeris did was actually summoning the VERY thing that could stop Meteor. A direct counter to his final blow. The party obviously had to struggle with a lot more things to finally reach the point of stopping them. She was much more threatening.
But again, this is all assuming that he/Jenova could kill them at any time - which I doubt.
MasterX
Zantetsuken
I agree with your theory, HighwindPilot, but I've got my own, however similar it may be.
From the start of the game, or rather, since the fall into the Reactor, he learned about everything about the Black Materia, and became arrogant BECAUSE of all this knowledge. Since he destroyed Nibelhiem, he knew Cloud would confront him no matter what.
With these two things in mind, he would also expect Cloud to fight Shinra, so he made use of that and decided to help Cloud with his cause, for one thing; to kill the president and allow Cloud to discover him, giving him a reason to leave Midgar. His search of the Materia had nothing to do with Cloud, but those two events happened in the same time, he made use of both of em.
This part is somewhat confusing, I wonder if Sephy KNEW that Cloud would progressively become stronger and somehow obtain the Materia for him, which explains the "puppet" thing. But, did he know from predicting Cloud's actions from the events of Nibelhiem? Did Sephiroth know that Zack's death would happen? Or, was this a happy coincidence for him? But, if he could predict the future, he would have known that he would die during the final confrontation.
We know about the famous "Alien Jenova Theory", but did Jenova have the ability to predict the future? Somehow, she knew that everything would happen, but the "how" is kinda fuzzy. We don't learn that much about Jenova in the first place, because the story revolves around Cloud and Sephiroth, so it's debatable. The only thing known about Jenova is that her cells can be used to create stronger soldiers and the inhabitants of her cells consider themselves a "family", like with the antagonists of Advent Children.
Ignoring the characters' motives, pasts and feelings for each other, Jenova, Sephiroth and Cloud all created a crisis that would destroy the world, and would redirectly save it, with the help of Aeris.
I'll shut up for now, as I've discussed more than Sephioth's motives, but felt like talkin.
From the start of the game, or rather, since the fall into the Reactor, he learned about everything about the Black Materia, and became arrogant BECAUSE of all this knowledge. Since he destroyed Nibelhiem, he knew Cloud would confront him no matter what.
With these two things in mind, he would also expect Cloud to fight Shinra, so he made use of that and decided to help Cloud with his cause, for one thing; to kill the president and allow Cloud to discover him, giving him a reason to leave Midgar. His search of the Materia had nothing to do with Cloud, but those two events happened in the same time, he made use of both of em.
This part is somewhat confusing, I wonder if Sephy KNEW that Cloud would progressively become stronger and somehow obtain the Materia for him, which explains the "puppet" thing. But, did he know from predicting Cloud's actions from the events of Nibelhiem? Did Sephiroth know that Zack's death would happen? Or, was this a happy coincidence for him? But, if he could predict the future, he would have known that he would die during the final confrontation.
We know about the famous "Alien Jenova Theory", but did Jenova have the ability to predict the future? Somehow, she knew that everything would happen, but the "how" is kinda fuzzy. We don't learn that much about Jenova in the first place, because the story revolves around Cloud and Sephiroth, so it's debatable. The only thing known about Jenova is that her cells can be used to create stronger soldiers and the inhabitants of her cells consider themselves a "family", like with the antagonists of Advent Children.
Ignoring the characters' motives, pasts and feelings for each other, Jenova, Sephiroth and Cloud all created a crisis that would destroy the world, and would redirectly save it, with the help of Aeris.
I'll shut up for now, as I've discussed more than Sephioth's motives, but felt like talkin.
Omnislasher483
Posterboy for FFVII
Highwind Pilot has already done a great job explaining Sephiroth's motives. Let me see if I can clear any other fuzziness that's left about Sephiroth's motives.
As stated earlier, Sephiroth's original motive was a revenge. Though he didn't know it at the time, it was a misguided motive due to the fact that in the Shinra Mansion basement, he was reading Professor Gast's reports, not Hojo's. If you did get to see Ilfana's (Aeris' mother) interview with Gast, you'll learn that at the time, Gast was conducting the research independent from Shinra. Prior to his interviews with Ilfana, he too believed that Jenova was an ancient. When Hojo busted in, he (I assume) recorded the files and data Gast had collected, and studied them for himself without divulging any of the information to Shinra.
When the whole Nibelheim fiasco took place 5 years prior, Sephiroth was cast away into the lifestream with Jenova's head. I can only speculate that at some point during those 5 years, two things happenned;
One: Sephiroth gained the knowledge of the lifestream, and the with that the knowledge of the ancients. With that he probably learned what Jenova really was, and what he really was as well.
Two: He probably began to outwill Jenova, beginning to get her to do his bidding rather than the other way around. My argument for this would be that in Nibelheim, Sephiroth wanted to re-take the world for his 'mother', and after being in the lifestream for 5 years he fashioned a new goal with the knowledge of the lifestream, but this plan involved him becoming a god and the ruler of the world, not Jenova.
Afterwards, the will of Sephiroth, not Jenova took command of the body of Jenova at the Shinra building, changing into who everyone perceived was Sephiroth.
At this point of the game, Sephiroth has become in my opinion, corrupted by all the knoledge and power from the lifestream. Therefor, as a true knoledge and power addict, he seeks more of it. He devises a plan to concentrate ALL the planets spiritual energy at one focal point, where he will then merge with it absorbing all the power and knowledge the lifestream has to offer.
Getting a little more intuative with Advent Children, Sephiroth states that he wants to use the planet as a vessel and travel to new worlds, essentially merging with their lifestreams as well.
One way to look at it, if you're into Marvel Comics, is that Sephiroth wants to be the equivolent of Galactus Devour of Worlds.
As stated earlier, Sephiroth's original motive was a revenge. Though he didn't know it at the time, it was a misguided motive due to the fact that in the Shinra Mansion basement, he was reading Professor Gast's reports, not Hojo's. If you did get to see Ilfana's (Aeris' mother) interview with Gast, you'll learn that at the time, Gast was conducting the research independent from Shinra. Prior to his interviews with Ilfana, he too believed that Jenova was an ancient. When Hojo busted in, he (I assume) recorded the files and data Gast had collected, and studied them for himself without divulging any of the information to Shinra.
When the whole Nibelheim fiasco took place 5 years prior, Sephiroth was cast away into the lifestream with Jenova's head. I can only speculate that at some point during those 5 years, two things happenned;
One: Sephiroth gained the knowledge of the lifestream, and the with that the knowledge of the ancients. With that he probably learned what Jenova really was, and what he really was as well.
Two: He probably began to outwill Jenova, beginning to get her to do his bidding rather than the other way around. My argument for this would be that in Nibelheim, Sephiroth wanted to re-take the world for his 'mother', and after being in the lifestream for 5 years he fashioned a new goal with the knowledge of the lifestream, but this plan involved him becoming a god and the ruler of the world, not Jenova.
Afterwards, the will of Sephiroth, not Jenova took command of the body of Jenova at the Shinra building, changing into who everyone perceived was Sephiroth.
At this point of the game, Sephiroth has become in my opinion, corrupted by all the knoledge and power from the lifestream. Therefor, as a true knoledge and power addict, he seeks more of it. He devises a plan to concentrate ALL the planets spiritual energy at one focal point, where he will then merge with it absorbing all the power and knowledge the lifestream has to offer.
Getting a little more intuative with Advent Children, Sephiroth states that he wants to use the planet as a vessel and travel to new worlds, essentially merging with their lifestreams as well.
One way to look at it, if you're into Marvel Comics, is that Sephiroth wants to be the equivolent of Galactus Devour of Worlds.