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