So I have been trying to solve monsters spawning at my friends and our square where we have a fountain and some buildings surrounding it , we have tried lighting up the areas with lights but still momsters are spawning so we put the lights closer to each other to the point you would only see the lights we placed (redstone lamps with daylight censor on top). Bit that just didn't look good because now you only see lamps. So our solving of this problem was placing torches under the ground and then fill up the path with half slabs so the light shines through the ground, putting a high enough level light over the whole floor (atleast you would think that). We are now at a point in the game where the spawns are just out of control, monster are not even spawning on the lighted paths, they now even spawn in our buildings surrounding them. We would love if there could be checked in to because we are out of options.  If neeeded I could see for some screenshots. But it would take a little time but if needed just say the word.