Here is the full list of all 23 Forager achievements worth 1,000 gamerscore. It takes around 40-50 hours to unlock all of the achievements on Xbox One.
Mine the giant crystal
Activate a droid
Complete the Skull Maze
Fail miserably at a trivia minigame
Own 10 lands and 5,000 coins
Gather royal steel or royal clothing
Have one of each gem in your inventory
Complete the Ancient Tomb
Complete the Crystal Cave
Complete the Fire Temple
Build 200 structures
Complete every museum bundle
Learn every skill
Buy every land
Open every big treasure chest
Collect every tool and weapon
Collect every accessory
Collect every seal
Collect every artifact
Achieve every other feat
Reach Void level 30
Have 1,000,000,000,000 coins
Own 100 nuclear structures at once