Here is the full list of all 20 Santa Protects the Christmas Tree achievements.
Defeat 10000 snowmen with snowballs.
Return 1000 stolen presents to the Christmas Tree.
Play and finish 25 games.
Unlock all Upgrades.
Defeat 10000 snowmen with Flares.
Finish a level without moving.
Pick up 1000 special present power-ups.
Run 42 kilometers with Santa.
Defeat 2500 snowmen with Bubbles.
Play and finish a game on all four levels.
Achieve 5000 score in a single game on Fancy Forest.
Protect the Christmas Tree for more than 20 minutes in a single game.
Achieve 10000 score in a single game.
Defeat 2500 snowmen in a single game.
Defeat 30 snowmen with a single Flare.
Achieve 5000 score in a single game on Peaky Point.
Play 1 hour with the game.
Achieve 5000 score in a single game on Wonder Village.
Achieve 5000 score in a single game on Powdering Peninsula.
Play and finish a game on any level.