Here is the full list of all 39 It's Quiz Time trophies - there are 22 bronze, 12 silver, 4 gold and 1 platinum.
Unlock every trophy in It's Quiz Time
Complete a game with 8 players
Complete 30 games with friends
The same player works alone against a team of two or more players in Showdown 5 times
The same player answers every question correctly during All in Order
The same player correctly predicts that everyone will answer incorrectly during Trust or Bust
No-one answers correctly during Trust or Bust
Best friend fails to correctly predict player's answer in Best Friends Forever
Everyone answers correctly in Best Friends Forever, apart from the best friend
Play on December 25th
The leader beats a team of two or more players in Showdown
Play on October 31st
All players in a 4-player multiplayer game finish with over 7,500 points
The same player is chosen as the best friend by all players in a round of Best Friends Forever
A team of two or more players beats the leader in Showdown
A new player wins the game
The same player answers every question incorrectly during All in Order
The same player wins three games in a row
A player answers correctly during Trust or Bust when all other players predicted otherwise
A clue is removed during Describe It! after someone calls 'Shenanigans!'
A player scores over 9,999 points in a multiplayer game
Complete 10 games with friends
All players answer every question correctly during the Starter Round
A player guesses only one clue during Describe It!
A player correctly guesses every clue for a subject in Describe It!
Someone joins mid-game
The same player correctly predicts that everyone will answer correctly during Trust or Bust
A player correctly answers all specialist subject questions during The Big Finish
Answer every question in a game of Solo Score Attack but end with zero points
A player goes from last place after the first round to winning the game
Play two back-to-back games with the same players
All players choose the same specialist subject during The Big Finish
Score over 8,000 points in the Solo Score Attack
The same player is leading at the end of every round and wins the game
Complete a game with friends
A player scores over 450 points on a single question in The Big Finish
No-one answers incorrectly during a round of Connections
Someone calls 'Shenanigans!' during Describe It!
Complete a game of Solo Score Attack