Raid Player Bases / Monster Raids

This idea uses the raid mechanic already implemented into the 1.14 snapshots, and focuses it onto Players. The idea is that at random intervals in the Minecraft world, an announcement might go into a Player's chat, saying something like "Your base is being raided by Monsters!" with the last Bed the Player slept in as the focal point (another way of looking at it is the Player's spawn point). The player would have about two to five real-time minutes to prepare before Monsters appropriate to the situation start to spawn. If the Player's base is a subterranean, Monsters like Cave Spiders, Silverfish, Creepers, Skeletons, and Slimes could spawn. For surface bases, Monsters such as Zombies, Skeletons (mounted on Skeleton Horses or Spiders), Spiders, Creepers, and Endermen could spawn. Then, for areal bases, Nightmares and Endermen could spawn. Spawning could ignore light levels, or set the maximum level to be above 7; needless to say, the Monster Raids would take place at night. "Leader" monsters could wear special banners with the Skull and Cross bones template printed on, wearing the banners on their head; killing the Leaders could result in a special, Monster Raid-only drop such as an tool, weapon, or piece of armor with special enchantments applied (example might be an Iron Sword with Smite IX, or a Golden Pickax with Efficiency VIII).