Here is the full list of all 24 Soda Dungeon achievements. It takes around 60-80 hours to unlock all of the achievements on Windows.
Win a battle by only defending.
Complete 50 levels with only one Soda Junkie.
Complete 100% of the bestiary.
Complete dungeon level 1000.
Complete dungeon level 750.
Steal essence from an enemy.
Complete dungeon level 500.
Reflect 100 damage from a single attack.
Find a legendary item.
Hope you're hungry.
Complete dungeon level 250.
Sell 100 items.
Purchase all basic sodas.
Complete 100 levels in one trip.
Have one Knight defend for another Knight.
Complete dungeon level 100.
Find a rare item.
Inflict burn, sleep, poison, and confusion on one enemy.
Enter a battle in the Arena.
Complete 50% of the bestiary.
Slay 500 enemies.
Slay 10 bosses.
Discover and explore an alternate path in the dungeon.
Complete your first dungeon trip.