Here is the full list of all 24 Dungeons & Dragons: Chronicles of Mystara achievements.
Complete Tower of Doom
Reach Overall Player Level 5
Complete 1 Challenge Tier of “Slick Hammers”
Complete 1 Challenge Tier of “Pointy Things and Slings.”
Kill 30 Enemies of Any Type
Complete Shadow over Mystara
Kill 300 Enemies of Any Type
Kill 1000 Enemies of Any Type
Complete all Tier 1 Challenges
Complete all Tier 2 Challenges
Complete all Challenges
Gather all Treasures
Gather 10,000 Gold (SP)
Reach Overall Player Level 10
Reach Overall Player Level 20
Complete 1 Challenge Tier of “Fry ‘Em Up.”
Complete 1 Challenge Tier of “Paralyzation Nation.”
Complete all 3 Tiers of the Challenge "Till Death Do Us Part"
Complete all 3 Tiers of the Challenge "Petting Zoo."
Complete all 3 Tiers of the Challenge "Curb Stomp-A-Thon."
Complete all 3 Tiers of the Challenge "So Desperate!"
Complete all 3 Tiers of the Challenge "Loot Master."
Complete all 3 Tiers of the Challenge “Spellcaster.”
Complete all 3 Tiers of the Challenge “Help Wanted.”