Here is the full list of all 20 The Jackbox Party Pack 8 achievements.
Got a Rainbow Bonus in all three rounds
Earned the power slice every round in a single game
Earned over 10000 points from a single slice
Played the game at midnight
An Accomplice named Schmitty was murdered
Played Friend Mode
Got two Synergies in one round
Poked the logo 40 times
Your team went an entire round without selecting an incorrect door
Fooled the same player three times in a game
Used all three colors in an animation
Used the word "accomplishment" in a title
Spun the wheel when all players had enough points to win the game
Had your question answered two games in a row
Played a game every weekday between 9am and 5pm
In round one, picked the eighth place door on first guess
Won a game by yourself against nine people
In Streamer Mode, played against an audience of 1,000 or more
At least one detective got every case right, including Cold Cases
A single Accomplice received 10 murder attempts