Here is the full list of all 71 Slayin 2 achievements.
Clear the Grasslands area.
Clear the Forest area.
Clear the Dark Forest area.
Clear the Outer Castle area.
Clear the Castle Courtyard area.
Clear the Graveyard area.
Clear the Southern Grasslands area.
Clear the Lagoon area.
Clear the Lake area.
Clear the Echoing Cavern area.
Clear the Eastern Grasslands area.
Clear the Forgotten Desert area.
Clear the Desert Ruins area.
Clear the Volcano West area.
Clear the Volcano East area.
Clear the Burned Forest area.
Clear the Poison Forest area.
Clear the Witch Coven area.
Clear the Castle Dungeon area.
Clear the Ancient Library area.
Clear the Ancient Cave area.
Clear the Ancient Vessel area.
Clear the Dragon Rock area.
Add the Princess to your party.
Add the Ninja to your party.
Add the Sorceress to your party.
Add the Lancer to your party.
Add the Automaton to your party.
Add the Archer to your party.
Add the Bomber to your party.
Fully upgrade a Knight weapon.
Fully upgrade a Princess weapon.
Fully upgrade a Ninja weapon.
Fully upgrade a Sorceress weapon.
Fully upgrade a Lancer weapon.
Fully upgrade a Archer weapon.
Fully upgrade a Bomber weapon.
Rebuild all buildings in the Town.
Buy a charm from the Charm shop.
Have an item examined in the Antique shop.
Fully upgrade your Slay Spark bars.
Earn a Bard Song.
Earn all the Bard Songs.
Find the Royal Key.
Find the Ancient Rod.
Find the Dwarven Lantern.
Find the Ancient Whistle.
Find the Ancient Core.
Find the Dragon Compass.
Beat the game and see the good ending.
Beat the game and see the bad ending.
Clear Arcade mode with any character.
Get a Slain combo of 500 in Arcade mode.
Get a Slain combo of 1000 in Arcade mode.
Get a Slain combo of 3000 in Arcade mode.
Spin the mill wheel with wind magic.
Discover the Princess Club
Discover the Treasure Weasel.
Earn the Legendary Sword by defeating the Flame Witch without taking damage.
Earn Goldenmane's Horn by finishing a desert area without killing any Knightmare enemies.
Earn the Kitsune Scroll by defeating 50 enemies in a row without taking damage as the Ninja.
Earn the Lost Magic by defeating 20 enemies in the air without landing as the Sorceress.
Earn the Steel Arrow by firing 30 arrows without missing a target as the Archer.
Clear all of Princess Green's quests.
Earn the Spicy Charm from Princess Violet by collecting food with full health.
Earn the Dark Pact Pendant from Princess Magenta by defeating 3 bosses without taking damage.
Discover the path to the Castle Dungeon.
Discover the path to the Ancient Library.
Discover the path to the Ancient Cave.
Discover the path to the Ancient Vessel.
Discover the path to Dragon Rock.