Here is the full list of all 26 Lightyear Frontier achievements.
Plant your first seed.
Scare away 10 animals.
Remove 10 Noxious Slimes.
Plant 100 seeds.
Plant 500 seeds.
Plant 1000 seeds.
Remove 50 Noxious Slimes.
Remove 150 Noxious Slimes.
Build the radio tower.
Remove 100 Noxious Weeds.
Remove 300 Noxious Weeds.
Remove 700 Noxious Weeds.
Increase Homestead Coziness to 1.
Increase Homestead Coziness to 2.
Increase Homestead Coziness to 3.
Explore a ruin.
Explore 7 ruins.
Explore the vault in Outset Grasslands.
Feed an animal for the first time.
Feed 20 animals.
Feed 50 animals.
Restore all regions in Outset Grasslands.
Restore a region.
Spray water at another player.
Get an upgrade at the Upgrade Depot.
Get 10 upgrades at the Upgrade Depot.