Sagat, THE fighting game Muay Thai fighter. He first debuted in the very first Street Fighter game as the final boss. At this point, he's also affiliated with M. Bison and Shadaloo as one of their champions (along with Vega and Balrog, who would later be playable in Alpha 3). He constantly trains to become better and stronger.

As a honest Muay Thai fighter, he's slow in movement, normals and specials but he's very, very strong.

For specials, he has his Tiger Crush, which is a powerful and quick attack that makes him move a little forward easier, along with characters like Ryu and Ken, he also has his own fireball and uppercut moves (Tiger Shot and Tiger Blow), which are actually based of Ryu, since Sagat is one of, if not the most important rival he has ever had in the series (story-wise).

(I will put his secret rival dialogue here once I get into that)

His final battle is against noone other than Ryu, in Australia, in a blank grass while it's raining. Let me yap more about it because it really deserves that amount of recognition.

Sagat has been constantly seeking revenge against Ryu because of his scar, which Ryu has given him due to his misuse of the Satsui no Hado and his Metsu Shoryuken. In this game, Sagat has the already shown special intro animation against Ryu to reflect this.

This battle is actually unique because it's the only one with an special stage, and said stage directly references their fight at the very start of Street Fighter II: The Animated Movie.

The theme for this battle has a constant leitmotif of Sagat's Theme.

Ryu's CPU for this battle is really, really harder than normal. He will keep putting pressure on Sagat with bread and butter combos, his Alpha Counters whenever you try to attack him, Hadoukens whenever you're relatively far from him and Shoryukens whenever you try to start a combo via air normals.

His ending in this game actually foreshadows his brand new uppercut in Street Fighter II; his Tiger Uppercut, which replaces his Tiger Blow.

Other than that, as I said i'm still looking forward to know more about his story throughout the trilogy since it's very important. What little information I'm aware about is that his patch in the eye was not caused by Ryu, but rather was a severe injury Dan's father, Go Hibiki, caused him in said eye, which led to Go's death at the hands of Sagat.

Sagat has an EX version in Alpha 2: Gold, which gives him access to faster recovery and start-up on his Tiger Shots, and also gives him access to many 2-hit normals.

In Alpha 3, he has 3 different intro animations against Ryu depending on what Ism he's using, his X-ism and V-ism special intros directly reference an iconic, promotional artwork of Sagat with someone who looks very similar to Ryo Sakazaki from Art of Fighting, completely defeated, demonstrating the rivalty between Capcom and SNK.

It's all about the fight.