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