Here is the full list of all 13 Causality achievements.
Complete every level in Causality
Kill the stalker
Complete the fourth level set
Complete the third level set
Complete the level in 16 segments
Complete the level using only 3 actions
Complete the second level set
Complete the level using only 4 actions
Complete the level using only 5 actions
Complete the first set
Complete the level in 10 segments