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