Here is the full list of all 30 Bugsnax achievements worth 1,000 gamerscore. It takes around 15-20 hours to unlock all of the achievements on Xbox One.
Complete the main story of Bugsnax.
Catch 100 unique species of Bugsnax.
Complete all of the side quests.
Fully transform every Grumpus.
Defeat all of the Legendary Bugsnax.
All of the Grumpuses survive.
Watch all of Lizbert's video diaries.
Interview every Grumpus.
Donate max amount of Bugsnax to Gramble's ranch.
Return every Grumpus to Snaxburg.
Catch 50 unique species of Bugsnax.
Fully transform a Grumpus.
Scan the Snaxsquatch.
Transform a Grumpus with Scoopy, Banopper, and Cheery.
Stun a Bugsnak with the Trip Shot attached to your Buggy Ball.
Empty one biome of all its Snakpods.
Catch your first Bugsnak.
Transform a Grumpus with Bunger, Fryder, and Sodie.
Stun a flying Bugsnak by launching another Bugsnak at it.
Solve the secret of the lava cave or the secret of the dunes.
Catch more than one Bugsnak in your Snak Trap at once.
Scan a Grumpus after saucing them with cheese.
Steal Beffica's diary from her cave.
Catch 25 unique species of Bugsnax.
Find your way to Snaxburg.
Check behind the waterfall for secrets.
Complete the adventure at Broken Tooth.
Collect 10 hats.
Fully furnish your hut.