Here is the full list of all 15 Biglands: A Game Made By Kids achievements.
Die 300 times
Beat the Game
Fully Upgrade All Weapons
Fully Upgrade Any Weapon
Beat Humanya Ka,olana
Kill 2000 monsters
Collect 7000 items
Beat the Graveyard
Attack 10000 times
Jump 10000 times
Beat Dr. Evil Herobrine's Lab
Beat Twilight Forest
Beat Mars
Beat Cloud Island
Beat Lava Land