Here is the full list of all 26 Ampersat achievements.
Fill the Bestiary
Gain all Perks
Beat the Well's 100th level
Open the Portal to Lord Z
Capture all Bonus Words
Gain 3rd Ring Bonus Perk
Defeat all Dungeons
Fully Upgrade Armor Shop
Make the Gem Merchant appear
Fully Upgrade Weapon Shop
Fully Upgrade Well
Defeat a Tower
Gain 2nd Ring Bonus Perk
Fully Upgrade Freya's Statue
Fully Upgrade Skadi's Statue
Return all Lost Items
Fully Upgrade Inn
Gain 1st Ring Bonus Perk
Sniff out all Secret Chests
Defeat a Dungeon
Open the Well
Consult the Bestiary
Find a Secret Chest
Gain a Rank
Capture a Bonus Word
Ostensibly read the "How To"