Here is the full list of all 50 Echoes III achievements.
GET HIT 25 TIMES
SURVIVE A BLACK HOLE FOR 30 SEC
KILL THE SUN IN LESS THAN 4 MIN [VIPER SYSTEM]
KILL 2 PLANETS BEFORE GETTING HIT
KILL A SUN WHILE ENERGY >90%
CRASH INTO 10 MOONS [VIPER SYSTEM]
SCORE 1M POINTS [CLASS 1C SYSTEM]
COLLECT 75 BONUS STARS IN LESS THAN 60 SECS
KILL SUN IN LESS THAN 2 MIN [HADES SYSTEM]
SHOOT A BLACKHOLE 1982 TIMES
GET 2000 KILLS
GET 5000 KILLS
KILL THE SUN [ANARCHY SYSTEM]
EXPLODE 50 BOMBS
KILL A SUN WITHOUT USING HEALTH POWERUPS
KILL THE SUN IN LESS THAN 4 MIN [CLASS 1C SYSTEM]
SURVIVE FOR 3 MIN [VIPER SYSTEM]
KILL 2000 ASTEROIDS
GET HIT 50 TIMES
KILL 250 ICE CUBES [SIBERIAN SYSTEM]
KILL 33 SHOOTING STARS
SURVIVE FOR 1 MIN WITHOUT FIRING
GET CLOSE TO DARK MATTER X20
GET A 50X MULTIPLIER
PICKUP 2000 PIECES OF BOMB FUEL
GET A X25 MULTIPLIER [ANARCHY SYSTEM]
SURVIVE FOR 666 SECS [CLASS 1C SYSTEM]
KILL THE SUN [VIPER SYSTEM]
KILL 3 PLANETS IN LESS THAN 1 MIN
COLLECT 1234 BONUS STARS
KILL 200 OORT CLOUD ROCKS
SURVIVE FOR 3 MIN [SIBERIAN SYSTEM]
GET A X25 MULTIPLIER [VIPER SYSTEM]
DROP A TOTAL OF 75 POWERUPS
SURVIVE FOR 2 MIN [HADES SYSTEM]
COLLECT 666 BONUS STARS
KILL THE SUN [SIBERIAN SYSTEM]
RESCUE 5 MEN
KILL SUN IN LESS THAN 150 SEC [SIBERIAN SYSTEM]
LET A BLACK HOLE GO SUPERMASSIVE
GET 3000 KILLS
GET 5 MAN TRAPS ON SCREEN WITH 100% HEALTH
SURVIVE A BLACK HOLE FOR 90 SEC
LET A SUN LIVE FOR 1 MIN
SURVIVE FOR 1 MIN [HADES SYSTEM]
SURVIVE FOR 90 SECS [CLASS 1C SYSTEM]
COLLECT 9 BOMB POWERUPS
SCORE 1.5M POINTS [ANARCHY SYSTEM]
KILL THE SUN [HADES SYSTEM]
SURVIVE A BLACK HOLE FOR 3 MIN