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