Here is the full list of all 40 Lost Ruins achievements.
Arrive at the one true ending.
Complete Boss Mode.
Complete Hardcore Mode.
Deflect 20 enemy attacks with a Katana.
Complete Assassin Mode.
Complete Witch Mode.
Arrive at the end.
Discover another ending.
Visit every area.
Consume 100 Meat items.
Collect every piece of equipment.
Collect every weapon.
Defeat every boss.
Land 50 attacks on enemies by penetrating their shields.
Defeat 50 enemies with a Sledgehammer.
Open every treasure chest.
Defeat 5 Orcs.
Collect every record.
Collect every artifact.
Defeat Sadora the Ascetic.
Defeat 50 enemies with ice spells.
Collect every Spell.
Defeat 30 enemies with Runic spells.
Defeat 20 enemies by using traps.
Complete every quest.
Defeat 50 enemies with Fire spells.
Defeat 30 Plant monsters.
Inflict 30 critical hits with Throwing weapons.
Defeat 20 enemies with a Holy Sword.
Defeat 60 bugs.
Block 50 Attacks.
Defeat 44 enemies with Corpse Absorption spells.
Defeat 10 Banshees.
Unlock every art piece.
Earn 999 gold.
Hear all of the Goblin Merchant's tales.
Inflict 50 critical hits with a Bow.
Destroy 5 icons.
Defeat 66 Demon or Undead enemies.
Defeat 47 enemies with a Gladius.