Alright then. The special feature will be the lottery block. In exchange for a certain amount of emeralds, you can get random materials in the game. It will cost something to use, and depending on what you use as the currency, it will pull from a fair loot of resources. Example;insert a diamond, and get a chance for a diamond block, or even a nether star, but also have a chance to get some less valuable materials, like eggs or sticks. It will be re-usable. It will also have a cool down. You can use it 5 times every Minecraft day. Or it can be that this villager can spawn anywhere, even in other dimensions, without needing a village.