Here is the full list of all 21 Cornucopia Demo achievements.
Defeat the Spider Boss
Try Every Scratch Card
Earn 10,000 Gold
Catch your first Fish
Discover the Old Mines
Harvest your first Vegetable
Brush an Animal
Catch your first Large Fish
Bomb an NPC
Harvest your first Fruit Tree
Give your first Gift
Get Stuck in the Waterwheel
Harvest your first Berry Bush
Refine 10 Times
Pass out from Exhaustion
Plant your first Seed
Decorate your Home for the First Time
Feed Munger for the First Time
Open your first Letter
Steam Train was Spotted
Catch 10 Fish