Here is the full list of all 23 Downwell trophies - there are 5 bronze, 10 silver, 7 gold and 1 platinum.
Completed all other trophies.
Beat the boss (hard mode).
Beat the fourth area (hard mode).
Beat the third area (hard mode).
Beat the second area (hard mode).
Beat the first area (hard mode).
Complete an area without landing.
Have more than 5000 gems.
Complete a level without landing.
Beat the boss.
Have more than 3000 gems.
Land a 30 combo.
Land a 100 combo.
Beat the fourth area.
Beat the third area
Complete an area without taking damage.
Complete a level without killing any enemy.
Land a 10 combo.
Complete a level without visiting siderooms.
Complete a level without shooting.
Beat the second area.
Beat the first area.
Complete a level without taking damage.