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