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