Here is the full list of all 20 The Jackbox Party Pack 3 achievements worth 1,000 gamerscore.
Answered 5 Trivia Questions in a row correctly
Used all of your colors in a single drawing that then gets used on a shirt
Won all your battles in Round 1, but lose all your battles in Round 2
Guessed the exact percentage
Perfect guessing of higher/lower
Faker got through three tasks in a row without a single vote.
Played five games of Fakin' It in a row.
Caught the Faker on the first vote.
Voted against your own shirt in a battle
Picked top three answers in final round
Played 3 games in a row with the same players
Survived The Killing Floor 3 times in one game
Get a score of 25 or more in the Math Killing Floor
Guess within 5% of an audience's answer
Get a Super Quiplash!
Create a custom game
Write "gravy castle" and win a battle with it
Play 40 You Gotta Point tasks.
Get all the votes in a single battle in a 5+ player game
Be the creator of every shirt in the final gauntlet