Here is the full list of all 32 Len's Island achievements.
Die to Bees.
Defeat the Voidboar.
Lose 500 Coins on Blackjack.
Collect 50 Lightstone.
Plant 1,000 Crops.
Get 10 Blackjacks.
Buy the Voidpack.
Get Killed by a Tree.
Collect 1 Lightstone.
Kill 500 enemies.
Eat 50 Blue Berries.
Collect 20 Glass Bottles.
Get a Blackjack.
Kill 100 Enemies.
Do 100 rolls.
Collect some wood.