Alex is a a Dromaeosaurid, created from a fossil by Doctor Boskonovitch during Kazuya Mishima's control over the Mishima Zaibatsu. Doctor Boskonovitch wished to combine the genes from a martial artist and cross it with a wild animal, which spawned Alex and Roger The Kangaroo.
Alex made his first ever appearance in the second Tekken game, Tekken 2 of which he is a palate swap for Roger. He shares the same moves as him as well as his animated win poses in the game. To unlock Alex, the player needs to achieve a 'Great' in the final round in Arcade mode. In Alex's ending, he discovers one of his ancestors upon seeing a dinosaur fossil. He runs gaining speed and jumps into the air afterwards.
Tekken TAG Tournament
Alex also appears in the non-canonical game Tekken TAG Tournament as as palate swap for Roger. In his ending he plays the game "Rock, Paper, Scissors" with Yoshimitsu. Since he is wearing gloves, it will appear that he is always throwing rock. Yoshimitsu, knowing this, always throws "paper" to beat Alex.
Tekken TAG Tournament 2
After many years, Alex makes his return in Tekken TAG Tournament 2 of which he now has his own character slot instead of being a alternative pallet for Roger.
Alex's fighting style is Commando Wrestling which involves punches and grapples. It is similar to boxing, except there is grappling and throws involved. Alex seems to have a similar fighting style to Armor King, even adopting some of his throws and moves.
Tekken: The Motion Picture
Alex appears is the secret weapon unleashed by Heihachi Mishima and created by Lee Chaolan. Alex slays Anna Williams in the movie. The group of Alex dinosaurs also interrupts Jun Kazama and Kazuya Mishima's fight. Jun and Kazuya are forced to fight Alex themselves and Kazuya unleashes his Devil Gene upon necessity and kills the group of Alex. The movie is not considered canon though.
- Alex counts as a second player costume for Roger.
- His fighting style is identical to King's in Tekken 1 as well as Armor King in Tekken 2.
- Roger can be customised to look like Alex in Tekken 6.
- His sub-boss is Roger.