Here is the full list of all 54 The Dungeon Vendor achievements.
Win a 0% or less success fight with only bonus damage from enemy weaknesses
Lose to a roll of 5 or under
Create a weapon with a success percent of at least 300%
Create a weapon with a success percent of at least 500%
Win your first tie
Lose a 95% success chance fight
Win a fight by 1
Experience your first hero death
Have 2 heroes in a row die
Have 10 heroes die in one campaign
Build a weapon with 4 Legendary (red) materials and fail the forge
Reach the Ship of Tortured Souls
Reach the Dead Tides
Reach the Halls of the Dead
Reach Gord's Lair
Meet Your first ghost
Equip a ghost and have them win
Equip a ghost and have them lose... again
Get 2 legendary (red) drops in one level
Get your first boss trophy
Complete 100% matches in the forge
Find a match on first two tiles selected
Find five straight matches in the forge in one build
Lose 0 attempts in the forge
Make 5 matches at the forge without removing an impurity
Hit the maximum on the Anvil
Hit 3 Maximums on the Anvil in one build
Discover one of the dungeon Bosses weaknesses
Discover all of a single dungeon Bosses weaknesses
Discover all dungeon Bosses weaknesses
Spend 100 gold with the Merchant in one visit
Make all three impurity matches in one weapon build
Reroll the Merchant ten times in one visit
Buy out the Merchant's stock
Don't buy anything from the Merchant for a day
Don't buy anything from the Merchant for an entire playthrough
Give a Weapon a custom name
Earn every boss trophy
Have 1 of every metal at once
Have 1 of every hilt material at once
Have 1 of every element at once
Have 1 of every rune at once
Dye a Weapon
Make a profit of over 50 gold from one hero
Build a weapon with all Legendary (red) materials
Build a weapon with all Rare (purple) materials
Build a weapon with all Expert (blue) materials
Complete a playthrough without losing any heroes
Merchant shows up with all Legendaries (reds)
Improve a 50% Weapon to 100% at the forge
Get your first Legendary (red) item drop
Create a weapon named for the creator
Meet the time traveler
Meet your assistants true form