Here is the full list of all 29 Henry The Hamster Handler achievements.
Complete first five levels.
Fail to save 3 Hamsters in a row.
Retry a level.
Fail to save a single Hamster in a level.
Put out 500 fires.
Disable 450 electric traps.
Make 450 water crossings safe.
Disable 450 crushers.
Wind down 450 cranks to allow Hamsters to pass.
Teleport 500 Hamsters.
Inflate 450 Hamsters.
250 Hamsters killed by fire.
150 Hamsters killed by spikes.
Kill 50 Hamsters with your Hook.
200 Hamsters killed by crusher.
200 Hamsters killed by water.
200 Hamster killed by electricity.
Complete all levels.
Bop 50 hamsters in whack-a-hamster.
Bop 40 hamsters in Hamster Hunt.
Finish a game of hamster hunt with 80% accuracy (Minimum 10 hamsters bopped).
Send 6 hamsters in Hammy Says.
Earn 3 stars on 20 levels.
Hit the emergency stop button mid game.
Have a play session consist of over 1 hour.
200 Hamsters killed by turrets.
Disable 300 turrets.
Save all Hamsters on a level (After level 20).
Get at least one star on each level.