Here is the full list of all 26 Kittypocalypse achievements.
Kill 10 brittle kitties with a gatling in one level
Have 30 kittens frozen at once
Kill three kittens with one Annihilator shot
1.000.000 Damage Total
Lift 25 Panzer Kittens
Total damage over 3000000, in one campaign
Push a kittens to its death
Kill a kitty inside a blob 30 times during the lifetime of playing
Have all different types of minelayers at once
Have 30 kittens covered in acid at once
Have 30 kittens covered in oil at once
Have more than 5 Shredders at once
Have more than 5 fully upgraded fast missile towers
Hit a kitty in the air with a missile 10 times during the lifetime of playing
Beat any level using only laser towers
Ignite 25 kittens in one level
Beat any level using only tesla towers
Kill two blobcelerated kittens with one Annihilator shot
Kill a kitty within 2 seconds of it leaving its deployment shield bubble
Complete Easy Campaign
Complete Medium Campaign
Complete Hard Campaign
Complete the campaign on all difficulty levels
Killed over 1 mio kittens during the lifetime of playing
Kill 5 kittens with one Tesla charge
Killed over 100.000 kittens during the lifetime of playing