Here is the full list of all 78 The Witcher 3: Wild Hunt - there are Complete Edition achievements worth 2,000 gamerscore.
Kill 50 human and nonhuman opponents by striking them in the head with a crossbow bolt.
Collect all the cards in the Skellige deck.
Acquire all gwent cards available in the base version of the game.
Complete all witcher contracts.
Serve time in Toussaint.
Make an opponent suffer from bleeding, poisoning and burning simultaneously. Do this 10 times.
Use the Axii Sign to force one opponent to kill another. Do this 20 times.
Complete the contract on Therazane.
Complete the contract on Morvudd.
Kill 3 opponents with their own arrows.
Win all the horse races in the game.
Kill a frozen opponent with a crossbow bolt.
Be decorated with the Order of Vitis Vinifera.
Develop a mutation.
Collect all available Ofieri armor and horse gear, and at least one Ofieri sword.
Find all grandmaster diagrams for each witcher school.
Unlock the bonus for equipping all the witcher gear elements from one School.
Complete all fistfighting quests in Velen, Skellige and Novigrad.
Kill 20 cows.
Defeat Olaf, the Skellige champion of unarmed combat.
Use all available options for developing Corvo Bianco.
Be given Aerondight by the Lady of the Lake.
Obtain a flawless victory in all the competitions during the knights' tourney.
Help unite the warring vineyards and have a wine named in your honor.
Kill Golyat with a crossbow bolt to his eye.
Travel to the Duchy of Toussaint.
Defeat all the fallen knights and loot their campsites.
Have all possible Place of Power bonuses active at the same time.
Slide downhill uninterrupted for at least 10 seconds.
Finish the "Hearts of Stone" expansion.
Provoke all Iris von Everec's Nightmares into fighting you at the same time and defeat them.
Recreate all of Iris' nightmares in the Painted World.
Participate in all the activities at the wedding.
Buy all the items put on the block at the Borsodis' Auction House.
Kill the prince cursed into a toad.
Reach character development level 35.
Destroy all monster nests in the Velen / Novigrad region, or in Skellige.
Attack, counter, cast a Sign and throw a bomb (in any order) in under 4 seconds.
Kill 10 opponents by knocking them off somewhere high with the Aard Sign.
Be under the influence of seven potions or decoctions at the same time.
Ignite the gas produced by a Dragon's Dream bomb using a burning opponent. Do this 10 times.
Acquire all the Abilities in one tree.
Complete the contract on Sarasti.
Finish the game on the "Blood and Broken Bones!" or "Death March!" difficulty levels.
Finish the game on the "Death March!" difficulty level.
Finish the game on any difficulty.
Defeat Eredin.
Take part in the assassination of King Radovid.
Visit Tir ná Lia and convince Ge'els to betray Eredin.
Fill all mutagen slots.
Find Ciri.
Defeat Tybalt and win the gwent tournament held at the Passiflora.
Perform 10 effective counterattacks in a row without getting hit or parrying.
Bring all possible allies to Kaer Morhen for the battle against the Hunt.
Win a round of gwent with a total strength of at least 187.
Help Yennefer extract information from Skjall's body.
Complete the contract on the Woodland Spirit.
Complete the subplot about choosing Skellige's ruler.
Discover 100 fast travel points.
Win a round of gwent using only neutral cards.
Kill 2 monsters you have a contract on without using Signs, potions, mutagens, oils or bombs.
Find and free Dandelion.
Find and equip all the elements of one set of witcher gear.
Play three hero cards in one round of gwent and win the match.
Resolve the doppler problem in Novigrad.
Kill 50 opponents using the environment (e.g. swamp gas, insects or objects).
Defeat an opponent in a fistfight without taking any damage.
Kill 5 foes in a fight without taking damage (except for Toxicity) and without using the Quen Sign.
Find the baron's wife and daughter.
Collect the formulae for 6 different bomb types.
Kill 3 opponents in one fight using 3 different methods (swords, bombs, crossbow, Signs, etc.).
Destroy 10 monster nests using bombs.
Complete the contract on the shrieker.
Complete the subplot involving Keira Metz.
Kill at least 5 opponents in under 10 seconds.
Read 30 books, journals or other documents.
Find Yennefer of Vengerberg.
Learn 12 potion formulae.