Depends on the version,
NES: 2000
PS: 4000
GBA: 20,000
PSP: 20,000
As this question is kind of vague, I'll answer the two I can think of this question meaning:1. The first boss in any final fantasy game is Garland, who you fight at the very beginning of Final Fantasy 1.2. The first final boss in any final fantasy is Chaos, whom you have to destroy at the very end of the first FF.
Final Fantasy VI's boss theme is called Decisive Battle.
SpoilerChaos (who's actually Garland) is Final Fantasy I's final boss. Before Garland died in the beginning, he had traveled back 2000 years to conspire with the four Elemental Archfiends and gain immense power. Also in the PSP and iPod/iPhone versions, Chronodia, a new superboss, fights you at the Chaos Shrine after you beat the game.
Yu Yevon.
you fight it
yes he is the final boss you have to face.
Ozma is the hardest boss in the game
Nemesis
get the 7 chaos emeralds
The name of the last boss is Zeromus, an entity created out of Zemus' hate.
Get all the chaos emeralds and fight the final boss.
Marilith or Kary (name depends on version)