Here is the full list of all 22 Teabat! achievements.
Collect every Teapot in a single playthrough
Start an Adventure!
Purchase every cosmetic in Adventure Mode
Purchase every palette in Adventure Mode
Achieve 30,000 points in Arcade Mode
Achieve 60,000 points in Arcade Mode
Achieve an S rank in Adventure Mode
Complete Adventure Mode on any difficulty
Achieve 100% completion in Adventure Mode
Reach the end of the game in Arcade Mode
Play a round of Arcade Mode
Complete Time Trial mode with any time
Let Teabat sleep in another minute before starting the adventure
Complete Adventure Mode on Hard Difficulty
Complete Time Trial in under 20 minutes
Stay still long enough in Minty Meadow for a bird to perch on Teabat
Get approval from a Teavil Dead
Find the teapots stuck in the old fountain
Reach the top of The Great Trea in Camomile Forest
Draw the bridge over the Castle Moat
Find the underground tea oasis in Camomile Forest
Find the teapots stuck in the Royal Tomb Tower Bell