Here is the full list of all 25 Blair Witch achievements.
Become Carver
Find out what happened to Bullet.
Collect all victim's photos.
Collect all of the psychiatrist's notes.
Collect all wooden dolls.
Break 10 totems.
Pick up all the trash.
Let the VA know about the lumberjack's death.
Collect all dog tags of the fallen comrades.
Kill 10 monsters.
Pay your respects to sheriff Lanning.
Let Bullet bring you 10 things
Find out what happened to Peter.
Score 40 points in Cobra.
Make the pizza guy lose it.
Help Ellis to get his redemption.
End the game without killing any monsters
Patch things up with Jess.
Kill your first monster.
Collect the first dog tag.
Collect the first psychiatrist's note.
Walk 100 miles...
Pet the dog
Collect the first wooden doll.
Collect the first victim's photo.