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