You fight Yevon, who takes control of all your summons, so if you are like me and did not work on your summons then it should be a pretty easy fight. Oh yea it is impossible to die on that fight. If you die your whole party is brought back to life.
After you fight Sin you learn that Yu Yevon is behind Sin's rebirth.This leads the group to infiltrate Sin's body and battle Seymour and Jecht's imprisoned spirits. This is the end of Final Fantasy X, but there is a Final Fantasy X-2 that continues the story as Yuna looking for clues to Tidus's survival.
You go inside it and kill Jecht and Yu Yevon.
you are allowed to pass to the next boss battle after a short cutscene and you can also get the hidden aeon in the cavern of stolen fayth (trying to avoid spoilers)
Vincent is in Final Fantasy VII and Dirge of Cerberus.
you cant play final fantasy 13 online but the new final fantasy 14 is coming out next year in march which is a online game
Well they just put out Final Fantasy XIII for Xbox 360 and PS3, Square Enix is currently working on Final Fantasy XIV, also for xbox 360 and PS3
Final Fantasy: Legend of the Crystals was the first TV spin off, which was a sequel to Final Fantasy V including 4 30 minute episodes. The next was Final Fantasy: Unlimited, a series with 25 episodes which was based on the common elements that appear across the Final Fantasy series. These are both anime series'.
when it will be next month.
in the second town you visit next to cid
Go across the river to Niblehiem(sp?)
The next game in the series, Final Fantasy XV will be much more action oriented. Probably not the same as you are describing, but about as close as we'll probably ever get.
there is an underground tunal in the city right next to it after u find the mythril
Either this year or next year. I'm not exactly sure.
This depends entirely on which Final Fantasy or Final Fantasy Spinoff game you're playing. Go to any search engine (e.g. google) and type the name of your game and write 'walkthrough' next to it, e.g. "Final Fantasy 6 Walkthrough". However I would personally recommend going to www.gamefaqs.com and searching the site.
It was a prequal to FF7, which means there is no 'next' unless they remake FF7 or create a sequal to FF7, which there is no news of at this time.