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