Here is the full list of all 80 Gryphon Knight Epic: Definitive Edition achievements.
Complete the game on Squire difficulty
Complete the game on Knight difficulty
Complete the game on Epic difficulty
Defeat TreeStache
Defeat Simiel Totec
Defeat the Ifrit
Defeat Zafira Faris
Defeat the Frogmoth
Defeat Eugenia Frischengust
Defeat the Djur War Elephant
Defeat Asterion Hornedson
Defeat the Giant
Defeat Dawid Melekh
Defeat the Kraken
Defeat Lorraine Learn
Defeat the Magical Stone Dragon
Watch the secret ending
Defeat 2000 enemies with the Crossbuster
Defeat 300 enemies with the Qamar Sword
Defeat 300 enemies with the Muuk Bow
Defeat 300 enemies with the Kraft Staff
Defeat 300 enemies with the Skadi Lance
Defeat 300 enemies with the Eben Sling
Defeat 300 enemies with the Ryunabbi Cannon
Defeat 300 enemies with the Dragon Squire
Defeat 200 enemies with the Witch Coven Squire
Absorb 100 HP using the Vampire Squire
Use the Fairy Squire to revive
Use the Shield Squire protection 40 times
Collect 5000 gold in one stage
Defeat 20 enemies with 1 bomb
Defeat 20 enemies with one Berserk Potion
Take no damage and kill 10 enemies while shrunk
Buy and use every Squire
Buy and use every Potion
Find the Rune hidden in the Zafira Faris Stage
Find the Rune hidden in the Simiel Totec Stage
Find the Rune hidden in the Eugenia Frischengust Stage
Find the Rune hidden in the Asterion Hornedson Stage
Find the Rune hidden in the Dawid Melekh Stage
Find the Rune hidden in the Lorraine Learn Stage
Upgrade one weapon or rune to the maximum
Upgrade all weapons and runes to the maximum
Defeat every enemy type
Find and interact with all cameos
Defeat all bosses using only the Crossbuster
Take no damage in the K'aax Jungle (Knight or Epic Difficulty)
Take no damage in the Huh Kobold Village (Knight or Epic Difficulty)
Take no damage in the Al-Sharaf Desert (Knight or Epic Difficulty)
Take no damage in the Al-Sharaf Village (Knight or Epic Difficulty)
Take no damage at Simpeldorf Village (Knight or Epic Difficulty)
Take no damage in the Royal's Wizard Tower (Knight or Epic Difficulty)
Take no damage in the Dödlig Mountains (Knight or Epic Difficulty)
Take no damage at Asterion's Warcamp (Knight or Epic Difficulty)
Take no damage in the Midbar Savannah (Knight or Epic Difficulty)
Take no damage at Dawid's Temple (Knight or Epic Difficulty)
Take no damage at Turquoise Bay (Knight or Epic Difficulty)
Take no damage at Lorraine's Hideout (Knight or Epic Difficulty)
Take no damage in the Katharizes Ruins (Knight or Epic Difficulty)
Defeat the specter in the Tutorial Stage
Reach a 50 combo
Reach a 100 combo
Dash right before a shot hits you and escape
Play the entire game without buying upgrades or items and using only the Crossbuster (Knight/Epic)
Defeat one boss with his own weapon
Defeat a boss with only 1 HP left
Beat all stages of the game in less than 2 hours
Listen to all dialog from the Wizard and the Shopkeepper
Get all the rare potion drops
Silence the duckling!
Defeat 300 enemies with the Taa Lantern
Defeat 200 enemies with the Shadow Squire
Defeat the Wanyudo
Defeat Dorago Murasaki
Take no damage at Bamboo Forest (Knight or Epic Difficulty)
Take no damage at Eiko Castle (Knight or Epic Difficulty)
Find the Rune hidden in the Dorago Murasaki Stage
Defeat 400 enemies with the Amulet Avatar (Co-op)
Finish the game with the Amulet Avatar (Co-op)
Defeat a boss where all damage was dealt by the Amulet Avatar (Co-op)