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