Weekly/Holiday Special Mobs, and Mob Suggestions/Block Suggestions

Mobs that spawn in certain holidays or months that you can collect exclusive and rare item drops from if you get on your world at the time of the holiday/month. All of these mobs despawn (even with nametags) after the given date/time, giving you a limited amount of time to get the special mob drops, and making sure that you cant cheat the system by making your date and time go ahead, Although you would probably be able to get the item drops from them. Some mob ideas could also include adding some never before seen mobs, such as,  The Illusioner, which many people have been dying to see ingame, could spawn during halloween, or other types of new mobs such as bosses, etc. Some of these could also be more difficult to find during that holiday, spawning in specific biomes. I think groundhogs on groundhog day would be a funny idea, especially if they snuck up and ate your crops, but I dont think that would be implemented. They would have new mob drops only accesible via waiting for the holiday/week or creative mode. Also, similarly to the zombies that spawn with pumpkins that spawn on halloween, I would love to see blazes with this feature, although, they spawn with a "Burnt Pumpkin" which can be crafted into "Burnt Carved Pumpkin", and also made by smelting pumpkins. Including this, "Burnt Pumpkin Pie" and when you eat it, you either get fire resistance, or you start burning.  Also maybe some other features, including a iron golem that starts burning if you try to make it.