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