Here is the full list of all 38 Shield Cat Demo achievements.
Start a new game of Shield Cat.
Collect all Fish Scales in a single stage.
Collect all Big Jewels in a single stage.
Collect all Cat Coins in a single stage.
Defeat the Big Mushroom in the Lignum Woods.
Collect one Fish Statue.
Fill out the entirety of the map in a single stage.
Beat River Challenge 1 while getting all stars.
Complete a Marcus' Adventure challenge while collecting all the crystals.
Complete a hard Marcus' Adventure challenge while collecting all the crystals.
Complete a Red Gem challenge.
Collect all Fish Scales across 6 stages.
Collect all Big Jewels across 6 stages.
Collect all Cat Coins across 6 stages.
Collect 7 Fish Statues.
Fill out the entirety of the map across 6 stages.
Complete 5 Red Gem challenges.
Complete a Hexagon challenge.
Complete 3 Hexagon challenges.
Complete 5 Marcus' Adventure challenges.
Complete 10 Marcus' Adventure challenges.
Complete the Letter Toss challenge in the Lignum Village.
Complete the Minecart Challenge 1 while getting all stars.
Take a ride on the Roo Express.
Take a trip to the Cat Kingdom.
Play the game in a harder difficulty.