Here is the full list of all 12 Defense Technica achievements.
Unlock all stages.
Destroy more than 30 enemy units in 5 seconds.
Clear a stage with less than 5% Core HP remaining.
Get more than 150,000 points when clearing a stage.
Save more than 5000 resources when clearing a stage.
Let 5 towers get destroyed by enemies in one stage.
Sell more than 10 towers in one stage.
Make an enemy's path longer than 250 meters by blocking with towers.
Unlock all towers.
Check information on all enemies.
Clear a stage by building all types and all levels of towers.
Clear all stages with 100% Core HP.