Here is the full list of all 21 Golfie achievements.
Get a hole in one.
Finish on par.
Play at least 6 cards in a single turn.
Get a hole in none.
Use the 'Cheater' card 3 turns in a row.
Use 4 'Inflate' cards in one turn.
Equip one non-default customization in each category.
Gain at least 1000 coins in a single run.
Defeat Golfoe.
Complete all challenges.
Buy all items in a shop.
Buy something in the shop for 0 coins.
Collect 10.000 coins.
Complete 18 holes in a run.
Build a deck with at least 20 different cards.
Obtain at least 20 different perks in a single run.
Complete 50 Beach holes.
Complete 50 Floating Islands holes.
Complete 50 Dungeon holes.
Complete 50 Cherry Garden holes.
Complete 50 Cave Ruin holes.