Here is the full list of all 56 Mysterious Realms RPG achievements.
Complete a mission
Encounter an Event
Slay the first enemy
Complete a mission when one Hero is dead
Unlock every feature in the Town
Reach the maximum of enemy's Health modif.
Solve a riddle
Slay the First Warden
Slay Elemental Lord
Slay Grim Reaper
Slay Goblin King
Slay a hidden enemy
Solve 3 riddles
Solve 8 riddles
Slay 10 enemies
Slay 25 enemies
Slay 100 enemies
Pick up 10 salvage
Pick up 40 salvage
Pick up 100 salvage
Complete 10 missions
Complete 20 missions
Open 10 vases, barrels etc.
Open 50 vases, barrels etc.
Open 100 vases, barrels etc.
Teach Hero a skill
Teach every Hero 4 skills
Teach every Hero 6 skills
Slay a rare enemy
Slay 5 rare enemies
Slay 10 rare enemies
Light 5 torches
Light 50 torches
Light 100 torches
Drink 5 potions
Drink 15 potions
Drink 40 potions
Encounter a stranger
Encounter 3 strangers
Encounter 5 strangers
Pick up 30 gold
Pick up 100 gold
Pick up 200 gold
Eat 3 food
Eat 10 food
Eat 25 food
Examine 3 objects
Examine 8 objects
Examine 15 objects
Empower a Crystal up to 3 power
Empower every Crystal up to 3 power
Empower every Crystal up to 5 power
Encounter 10 Events
Encounter 25 Events
Complete the game without any Hero dying
Obtain every other achievement