Here is the full list of all 33 Young Souls achievements.
Defeat Dwarvengobben
Help the Professor to bury the Digger under rocks
Rescue the Professor
Complete the game at 100%
Kill Kah-Kon
Kill Shinjo
Upgrade a weapon to 6 stars
Kill Dinkoy
Clear all Catacombs
Beat Yarlanda in the last Mausoleum
Kill Fazmore
Open all gold key chests
Open all silver key chests
Clear all hard branches
Open all bronze key chests
Upgrade an accessory to its maximum level
Complete a dungeon without taking any damage
Ride a dragon for the first time
Kill Tetcha
Kill Marl
Equip an armor and helmet combo
Upgrade a weapon or armor
Beat Dinkoy
Block 10 attacks
Dodge an attack by rolling
Parry an attack
Kill a goblin for the first time
Earn 5 stars on a Happy Fit training session
Collect 25,000 gold
Collect 50,000 gold
Collect 100,000 gold
Finish the game at least in Challenging mode
Finish the game in Expert mode