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