Arena for Monster vs. Golem Fight
This is a battle arena where monsters can fight snow golems or iron golems.
Blacksmith
For example, a forge could be filled with an anvil, a pool of lava, and furnaces, and built of stone and iron grates.
Small greenhouse
An idea for a simple greenhouse. However, the fields must be planted and dismantled yourself.
House garden
Not sure what else you can fill space with in your home? Then simply turn the space into a garden!
