Here is the full list of all 15 Digging Dragon achievements.
save up 100 coins
save up 200 coins
save up 1000 coins
buy all the skins in the store
build the 10th floor of the tower
build the first floor of the tower
use a potion
defeat 100 enemies
defeat 50 enemies
defeat 10 enemies
win 50 skeletons
defeat Dungeon Lord
you did't defeat Dungeon Lord
complete the game
buy the first skin in the store