Here is the full list of all 14 Dig Dog achievements.
Die 1000 times
Complete a full loop in 3 minutes
Complete two loops
Collect 1000 bones
Collect 1000 coins
Unlock all warp bones
Complete a loop
Complete a loop without warping
Reach the Mountains
Kill 1000 enemies
Assist an enemy in killing another enemy
Reach the Hills
Purchase an upgrade
Reach the Desert