Here is the full list of all 27 Peregrin achievements.
Reach the final monolith
Possess every possible creature
Activate the last totem in your journey
Discover all investigation points
Possess a creature 50 times
Clear a battle zone using only a single heavy enemy
Spend 60 seconds on a single vista scene
Possess a creature 10 times
Complete Chapter 1 without dying
Kill an enemy using a sentry turret in Chapter 5
Complete the Chapter 3 generator puzzle first try
Complete the Chapter 5 plane flame puzzle first try
Make your way across Chapter 3's crucibles with 15 or fewer button presses
Reach the fifth monolith
Reach the fourth monolith
Possess a creature 100 times
Give yourself the upper hand in Chapter 2's final battle
Die 5 times
Activate 10 totems
Activate 20 totems
Discover an investigation point
Force an enemy to kill their ally
Activate 5 totems
Use a light enemy to kill a ranged enemy
Reach the third monolith
Reach the second monolith
Reach the first monolith