Here is the full list of all 55 Onimusha: Warlords achievements.
Complete the game on Normal without enhancing swords or using Jewels.
Complete the game on Normal without using herbs or medicine.
Complete the game on Ultimate difficulty.
Complete all stages of Oni Spirits.
Collect all Fluorite.
Find the beetle on the tree trunk.
Spot the flock of wild geese at dusk.
Absorb souls from carp.
Complete the game and get an S Rank.
Unlock Kaede's alternate outfit.
Complete the game in less than 3 hours.
Strike Marcellus's final form with a Deflect Critical attack.
NEW_ACHIEVEMENUse Magic Jewels to increase Magic Power to maximum._DESC_2_7
Strike a demon with Kaede's Special Attack.
Unlock Samanosuke's alternate outfit.
Defeat Fortinbras.
Obtain the Bishamon Sword.
Collect all maps.
Defeat Marcellus's final form.
Open the gate to the Demon World.
Use Power Jewels to increase Vitality to maximum.
Defeat Hecuba.
Solve all number puzzles.
Collect all files.
Solve all decoder boxes.
Obtain all armor for Samanosuke.
Defeat a demon by knocking it down the waterfall.
Use the Decorated Sword to enter the East Area.
Complete the second half of the Dark Realm.
Obtain all long-range weapons.
Enhance all swords to maximum.
Enhance the gauntlet to maximum.
Defeat Barabazuu.
Kill a demon with a battering ram.
Enhance all orbs to maximum.
Win a power struggle with a demon.
Complete the first half of the Dark Realm.
Obtain the Vision Staff.
Defeat Stylado.
Obtain the Sacred Knife.
Cut down bamboo in the bamboo forest.
Speak to the first and second old moth man.
Obtain the Rosary of Communication.
Unseal the path to the Keep Underground.
Obtain the Arashi.
Defeat Marcellus.
Save a soldier under attack by demons.
Solve the crest puzzle.
Enter the abandoned keep.
Obtain the Kouen.
Defeat Osric.
Enhance equipment at Magic Mirror.
Obtain the Shiden.
Use a Special Attack to kill a demon.
Use the gauntlet to absorb demon souls.