Here is the full list of all 37 The Lord of the Rings: Gollum achievements.
Dived a total distance of 2000 metres.
You looked at all interactibles in Gollum's cave.
You've died for the first time in Barad-dûr.
…to catch a fish, so juicy-sweet.
All Gollum choices.
All Sméagol choices.
You finished Chapter 1.
You finished Chapter 2.
You finished Chapter 3.
You finished Chapter 4.
You finished Chapter 5.
You finished Chapter 6.
You finished Chapter 7.
You finished Chapter 8.
You finished Chapter 9.
You finished Chapter 10.
You got the Grashneg trampled, drowned, and eaten.
One Collectible down.
You found 20 Collectibles.
Well done. You found all those useless things.
You threw 50 stones.
You stole food from Mell's table.
You completed the “Halls of Grond” without taking damage.
You found all food items at the bell tower.
Turn off 10 lanterns.
You rang all the bells at the bell tower.
You killed 10 Orcs.
You discovered all vantage points.
You fell into lava.
You fell for a distance of 40 meters and survived.
You completed the game without dying.
You saved the Cook, the Elf guards, and the Riddlemaster.
The Cook, the Elf guards, and the Riddlemaster all died.
You played the entire riddle game with Mell.
You turned Riddlemaster's painting seven times.
You jumped from the bell towers at the waterfalls three times.
You unlocked all achievements.