Here is the full list of all 21 Frozen Free Fall: Snowball Fight achievements.
Obtain a total of 500 Stars
Complete 50 Snowball Fights
Dodge 3 snowballs in a round
Beat your opponent with 10 different characters
Throw 10 snowballs in a match
Throw 3 super snowballs in a round
Combine 5 Double Glacier gems
Finish the first 100 Winter levels
Combine 10 Iceberg and Glacier gems
Combine 20 Windchill and Glacier gems
Obtain a total of 100 Stars
Combine 30 Windchill gems
Combine 15 Double Iceberg gems
Obtains 150,000 points on one level
Combine 25 Windchill and Iceberg gems
Obtain a total of 1 Million points
Obtain 50,000 points on one level