Yes, you can also see him in Kingdom Hearts 1 and 2.
Leon is Squall from FF8. Square-Enix + Disney changed his name because Squall is hard for little people to pronounce, the people who play Kingdom Hearts XD
There have been multiple characters named Leon in the FF games. Final Fantasy II: http://finalfantasy.wikia.com/wiki/Leon Leon was also an alternate-reality linked character to Squall in Final Fantasy 8. There have been other instances of 'Leon's in FF, but these are the most commonly known ones.
No, Leon is not a playable character in The After Years
Final Fantasy II. Note: The original Final Fantasy II wasn't originally released outside of Japan. When the American Final Fantasy II first came out, it was actually Japan's Final Fantasy V. Firion came from the Japanese Final Fantasy II.
The cast of Final Fantasy Origins - 2002 includes: Kenta Miyake as Gus (Final Fantasy II) Yukimasa Obi as Firion (Final Fantasy II) Norika Shitaya as Maria (Final Fantasy II) Takayuki Yamaguchi as Leon (Final Fantasy II)
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No, they're totally unrelated characters. Any confusion would be down to Squall taking on the name 'Leon' (from his surname) in one of the Kingdom Hearts games.
No, characters from the different 'main' Final Fantasy games are not related to the ones in others. They are totally different worlds and universes.
Depends which Leon you are even talking about: Squall (FF8/KH): 17 Leon (FF2): ?? (Although it's implied he's a teen)
Squall (Leon) Leonhart wielded the gunblade in kingdom hearts and final fantasy VIII.
No, Squall Leonhart does not die in Final Fantasy 8. Do you own the game? Why don't you just play it for yourself, and find out all of the cool stuff.
I believe the game you're referring to is Resident Evil 4, there is a character named Ashley (The President's Daughter) and the main character Leon (Leon .S. Kennedy) Stars agent. Otherwise I don't know of any Leon besides Squall - Who goes by Leon in Kingdom Hearts, but there is no Ashley in the game that I know of. There is also a Leon in Final Fantasy 2.
Kings of Leon