Here is the full list of all 46 Runbow achievements worth 1,000 gamerscore. It takes around 10-12 hours to unlock all of the achievements on Xbox One.
Play a Lot
Unlock every guest character
Get the Mimicry power-up 10 times
Get hit by lighting 10 times
Get the Swapper power-up 10 times
Win a tie-breaker
Play Arena
Play King Of The Hill
Land 5 super punches
Play a Run game
Do 20 taunts in one game and win
Land 20 hits in one game and win
Taunt 20 times
Beat 10 Adventures with a friend
Set the fun type to Maximum
Set the fun type to Kawaii
Be stunned when you get the trophy
Beat the Bowhemoth in 10 deaths or 20 min
Unlock all Gallery content
Beat the Bowhemoth
Beat the Bowhemoth in 60 deaths or 60 min
Beat all levels in Adventure mode
3 medal all levels in Adventure mode
Beat Adventure mode and defeat Satura
3 medal all of Monster Manor
Beat all of Monster Manor
Beat Satura in Monster Manor
Play a level in each Adventure map
Beat all of Break-Out
3 medal all of Break-Out
Beat Satura in Break-Out
3 medal all of Lost Luau
Beat all of Lost Luau
Beat Satura in Lost Luau
Fall to your death 20 times
Beat all of Forgotten Forest
3 medal all of Forgotten Forest
Do 10 Butt Pounds
Get 3 medals in 15 Adventure levels
Beat 100 enemies
Break 30 breakable blocks
Get 3 medals in 10 Adventure levels
Land one of each attack
Get killed by a laser
Beat Satura in Forgotten Forest
Spend more than 3 minutes in the air