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