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