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