Here is the full list of all 29 Sneaky Sneaky achievements.
Sneak Kill 3 enemies while they are eating bait in a single level.
Buy every shop item at least once.
Kill 2 enemies at once with a bomb explosion.
Consume 10 health potions.
Stay on 30 sand tiles with an enemy present.
Sneak Attack a sleeping enemy.
Complete the main campaign.
Collect every ruby.
Finish a level without killing any enemies.
Have 5000 Gold in your wallet.
Fully level up your stats.
Awarded for completing the City zone.
Kill an Archer with your bow and arrow.
Awarded for completing the Canyon zone.
Survive an encounter after being detected 3 or more times.
Kill an enemy with a spike trap and switch.
Feed a skeleton some bait.
Kill a Burrowing Skeleton with a bomb while its above ground.
Anger a Ham Troll into destroying 3 or more objects.
Lead an enemy to 3 consecutive search points by breaking jars.
Sneak Kill an enemy distracted by a jar.
Awarded for completing the Forest zone.
Land a Long Shot with the bow.
Destroy or Harvest 100 tiles. (Trees, Rocks, Barrels etc.)
Successfully land 5 'Sneak Kills' from a bush or hay in a single level.
Finish a level without being detected. (Excludes tutorial level)
Sneak Kill an enemy who is searching for you.
Execute 5 consecutive Sneak Kills in a single level.
Collect your first ruby.