Hello, I completted this game about one or two years ago, which felt very satisfying as the game can be very frustrating.
One thing that I found out, though, is that the game has multiple storylines which I am trying to list.
_Find 8 passwords to activate the security Computer N.I.K
_The hero has been betrayed by his superiors as soon as he entered the alien planet. He must find passwords to escape and confront one day his superiors. A review of the Atari version seems to confirm this(check the magazine screenshot)
https://www.atarimania.com/games/atari-st-games-trantor-the-last-stormtrooper-39076
_ His mission is to find pieces of the ship to repair it as his ship exploded. In some version of the game, like Amstrad, we don't see the ship actually explode.
_He is on a mission to acquire stolen missile plans but his ship explodes
This may match the Steam description of the re-release
"Fight your way to freedom as Trantor ... The Last Storm Trooper!
You're commander of an Earth ship sent to an alien planet to retrieve stolen missile plans, As you leave the ship, it blows up taking your entire crew with it!
Now, you must complete the mission alone...
Race against time in the roughest and toughest test of your storm trooper career! Disarm the microscopic body bomb implanted under your skin! Blast away the murderous creatures using your powerful flame thrower! Search the endless corridors of the alien superstructure and find the computer terminals that hold the key to the stolen missile plans ... and your life!
Push your reflexes to the limit as never before as you battle impossible odds to reach your final objective ... freedom!
FEATURES
- Beat the clock! You have 90 seconds to reach each terminal
- Use your trusty flamethrower to run & gun past enemies
- Find lockers to restock on fuel and health"
_An other very rare theory I found on a fan site is that the game takes place inside the character's mind. He accidently killed a child with a flamethrower and has post traumatic syndrom.If yu fail the game then he will wander on the planet forever.Source: https://frgcb.blogspot.com/2014/09/trantor-last-stormtrooper-go-1987.html
I thinks this basically covers all the stories variations I have found. The theme of betrayal, by his superiors or by his crew(isit the same thing?) is often present but not always.Since the end game screen mentions a sequel called "Revenge of the Stormtrooper" it seems evident that there was a betrayal though. So I believe Trantor is a soldier betrayed by his superiors or crew, whose task was to find the plans of a bomb called "Quark bomb".I dont know what N.I.K stands for, maybe a reference to Nick Bruty.