I have placed more than enough torches inside my house and yet every time i come back to it it is filled with mobs. FILLED. Like every time i need to do something in my house i first have to spend like 10 minutes killing all the mobs, its really annoying. Also slimes are not supposed to spawn on slabs yet i am constantly having them spawn in rooms that are made entirely from slabs.. Ive put torches literally like every 2 blocks on my island and it does nothing.. Whats the point of trying to build a good island if you have to ruin it with torches literally everywhere... (which doesnt even work)
When you do /is biomeset mushroom_island you need to warp somewhere (maybe tp to someone or just go to the shop) then go back to your island (then it takes real affect) and then kill the mobs. vwala. No more mobs should spawn.