A senior officer and ace pilot of the Gradosian militia who considered himself a rival of both Eiji &amp; Gale. Once having romantic interests in Julia, she immediately rebuffed him. A sadistic psychopath, Gosterro delights in killing to the extent where his lust for blood overpowers all needs and reason, forcing him to take the lives of his own wingmen. Deeply wishing to kill Eiji, he personally takes the assignment of stopping the rebel with his own SPT-BG-91U Bullgrenn.

The SPT Lazner is a super-powered, computerized Tracer robot. It is the strongest robot in the universe. The story's hero, Eiji, is the child of an earthman and an alien from another planet. He happens to find out about a conspiracy to destroy the earth. Using Lazner and with his friends’ help, Eiji decides to save his father's planet earth and fight against his mother's planet to achieve peace in space. 
 
The Story takes place in an alternate reality based in the year 1996, where humanity is advanced enough to develop long-range space travel. 
 
(SOURCE: AnimeNewsNetwork)

The Layzner OVA serves as an alternative version of the TV series. 
The first episode, titled "Eiji 1996", recaps the first part of the series (episodes 01-24). 
The second episode ("Le Caine 1999") takes place after a time skip, and contains episodes 26 through 37 (episode 25 of the TV series, being a recap itself, is skipped here). 
The final episode, "Seal 2000", is an expanded version of the final episode of the TV series (38) and features new animation and a longer epilogue.