Here is the full list of all 40 Rainbow Billy: The Curse of the Leviathan trophies - there are 27 bronze, 8 silver, 4 gold and 1 platinum.
Earn every Trophy.
Fight toxic masculinity and befriend Dragalant.
Face your fears and befriend Calypso.
Accept your other self and befriend Shadow Billy.
Raise 5 creatures' friendships to Level 2!
Raise 30 creatures' friendships to Level 2!
Raise 20 creatures' friendships to Level 3!
Raise 40 creatures' friendships to Level 3!
Raise ALL creatures' friendships to Level 2!
Flawlessly complete a difficult "Circle" attack minigame!
Flawlessly complete a difficult "Dodge" attack minigame!
Flawlessly complete a difficult "Line" attack minigame!
Flawlessly complete a difficult "Paddle" attack minigame!
Flawlessly complete a difficult "Slots" attack minigame!
Flawlessly complete 50 attack minigames!
Recolor five colors in one blow!
Collect 10 Thoughts.
Collect 25 Thoughts.
Collect 50 Thoughts.
Collect 75 Thoughts.
Convert a Thought into a Figment of Imagination!
Collect ALL Thought Upgrades!
Befriend all creatures.
Destroy 25 Objects!
Peek through the window...
Discover the broken warp pipe.
Climb to the highest point in each area of the World.
Break the Curse of the Leviathan and save the World.
Talk to all Kickstarter Backers characters!
Hear each and every one of the The Confessor's secrets.
Discover Disco Broccoli!
Glide using the Billy-Copter for more than 5 straight seconds!
Get reprimanded for punching barrel-kind.
Fast travel between two distant areas of the World.
Listen to Friend-Ship whistle for more than 5 straight seconds.
Catch 10 non-gummi items while fishing.
Catch at least one of each kind of fish!
Catch three different objects in one fishing session!
Dig up 15 buried treasures.
Own 500 coins or more at one time