Here is the full list of all 37 Steredenn achievements.
Finish the first loop.
Destroy the Astroworm.
Kill 1000 enemies.
Kill 500 fighters.
Destroy the Super Chabal.
Finish the game once.
Destroy the Nemesis.
Meet the Mothership.
Destroy the Mothership.
Destroy a Battleship boss.
Destroy a Carrier boss.
Destroy a Cruiser boss.
Beat the Red Baron
Destroy a Destroyer boss.
Destroy a Frigate boss.
Pick all Melee weapons.
Kill 250 enemies.
Destroy a Bomber boss.
Pick 15 differents weapons.
Kill 50 enemies.
Kill 2500 fighters.
Kill 10000 fighters.
Destroy 100 cargos.
Kill a spy with the flamethrower.
Pick all weapons at least once.
Pick all Energy weapons.
Pick all Bullets weapons.
Pick all Heavy weapons.
Pick all Bots weapons.
Defeat all the bosses in the Arena at least once.
Dies 50 times.
Try all upgrades.
Beat the game using the Blaster only.
Destroy the Alien ship.
Destroy the Old Friend.
Destroy the Garbage Collector.
Complete a boss rush.