Here is the full list of all 44 Secret Agent HD achievements.
Spend at least 60 seconds under the water
Destroy 10 mecha-spiders
L10 without killing any enemies and with a perfect health.
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Finish any level in under 60 seconds
Complete any episode without taking damage.
Complete any episode in one session without loading.
Collect over $1000000 worth of bonus items
Complete any episode on hard mode.
Finish any episode on HARD with 35 ammo or more
Complete any level without killing any enemies
Stack two barrels, one on another
Finish 5 custom maps from the Workshop
Finish Episode 4
Collect all island treasure.
Collect every flag in the game
Life is better in the hot tub.
Catch 50 hidden coin bags
Kill an enemy while wearing a jetpack
Collect 100 tombstones
Finish Episode 3
Hold 6 keys in your inventory at once
Get maximum rapid fire
Blow up enemy with a Dynamite
Get confused and slowed down at the same time.
Kill 50 Ninja's
Finish Episode 2
Use the teleporter 50 times
Collect 25 toothbrushes
Disable laser grid 20 timesCHIEVEMENT_DESC_23_16
Destroy 10 tombstones
Finish Episode 1
Collect All Magnifiying Glasses in any episode
Finish a level with an extra key in your inventory.
Collect SPY letters in wrong order
Finish any level
Finish any level with a perfect score
Collect all SPY letters in the right order
Die in water
Destroy crawler bot while in the air on medium or hard difficulty.
Complete all achievements.