Here is the full list of all 32 Spell Karts achievements.
Purchased an item in the store
Destroyed another kart
Destroyed 10 karts
Won a race
Bought 10+items in the store
Collected 10+ chests
Collected 25+ chests
Collected 50+ chests
Complete Dungeon Dash in 45 seconds or less
The Library is my home now
Destroyed 50 karts
Unlocked Adept Rank
Unlocked Enchanter Rank
Unlocked Mage Rank
Unlocked Necromancer Rank
Unlocked Warlock Rank
Win a race in `Wild West`
Win a race in `Party Party`
Win a race in `Boogie Bogs`
Win a race in `Vicious Vikings`
Win a match in `The Pit`
Win a match in `Pirate Island`
Win a match in `Ice Box`
Win a match in `Dingy Dungeons`
Win a `Dungeon Dash`
Win a match in `Crate Town`
Complete 10 quests
Complete 25 quests
Complete 50 quests
Complete 100 quests
Complete 250 quests
Win a match in `Hillsides`