Here is the full list of all 46 Lion Quest achievements.
Played Lion Quest VS on all of the multiplayer maps
Unlocked Wordsworth the Panda
Every item in the Lion Quest gift shop is sold out
Cleared intermediate mode in Lion Quest Arcade
Achieved a top three high score in Lion Quest Arcade (intermediate)
Achieved a top three high score in Lion Quest Arcade (beginner)
Played 10 games of competitive Lion Quest VS multiplayer
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Found all Keys
Unlocked Leslie the Tiger
Cleared beginner mode in Lion Quest Arcade
Played a game of Lion Quest VS against the A.I.
Cleared Level 1–9 as Mildred the Owl
Unlocked Roy the Pig
Found all Gems
Unlocked Tracy the Elephant
Cleared Level X3 – Patience
Cleared Level X2 – Turbine
Cleared Level X1 – Gauntlet
Unlocked Brendon the Cat
Found 1 Gem
Unlocked Mildred the Owl
Cleared Level 1–9 as Jethro the Lion
Cleared Level 8 – Secret Lagoon
Cleared Level 7 – Skull Island
Cleared Level 6 – Tidal Station
Unlocked Ronald the Bear
Unlocked Jefferson the Fox
Cleared Level 5 – Zen Garden
Found 1 Key
Cleared Level 4 – Outer Space
Cleared Level 3 – County Fair
Cleared Level 2 – Red Cube
Cleared Level 1 – Shooting Rockets
Cleared Level 1–9 as Jefferson the Fox
Cleared Level 1–9 as Ronald the Bear
Cleared Level 1–9 as Tracy the Elephant
Cleared Level 1–9 as Brendon the Cat
Cleared Level 1–9 as Leslie the Tiger
Cleared Level 1–9 as Roy the Pig
Cleared Level 1–9 as Wordsworth the Panda
Played 50 games of competitive Lion Quest VS multiplayer
Cleared advanced mode in Lion Quest Arcade
Cleared expert mode in Lion Quest Arcade
Achieved a top three high score in Lion Quest Arcade (expert))