Here is the full list of all 22 Spellspire achievements.
Beat the Ballistic Gel on 50th floor.
Beat the Goblin on 40th floor.
Beat the Carp Knight on 30th floor.
Beat the Unicorpse on 20th floor.
Beat the Armored Corpse on 10th floor.
Come up with a seven letter word without using dictionary books.
Come up with a ten letter word without using dictionary books.
Come up with an eight letter word without using dictionary books.
Come up with a nine letter word without using dictionary books.
Beat the Lard Corpse on 60th floor.
Beat the Royal Jelly on 70th floor.
Beat the Prince on 80th floor.
Slay the dragon at the top.
Complete star challenges for each of the floors.
Descend to dungeon level 10.
Descend to dungeon level 42.
Slay the chrome dragon in the dungeon.
Reach 150m distance in the dungeon.
Find 25% of the available words in a level.
Upgrade a legendary wand to maximum level.
Upgrade the luminous robe to maximum level.
Buy all hats.