Here is the full list of all 18 The Gallery - there are Episode 1: Call of the Starseed achievements.
Blink 1000 times.
Listen to all the tapes in the game.
Light 5 fireworks.
Complete Episode 1.
Complete the Laboratory level.
Complete the Lower Sewer level.
Complete the Upper Sewer level.
Complete the Beach level.
Complete the Tutorial level.
Pick up 4 items.
Start a fire on the Beach.
Shoot 3 bells with one clip.
Spend the night in the Beach tent.
Douse 6 candles.
Hold the radio on the Beach for three minutes.
Return all the starfish to the sea.
Smash 15 special bottles.
Sink 5 volleyball shots in the Beach hoop.