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