I've decided to share my idea and I'm sure some have similar ideas but, I think there should be an ore golem added into minecraft for the cave update(s).
So these golems are the size of nearly 2 blocks(1.5) and they basically take care of the ore. In a cave (mainly where diamonds are) you find an ore for an example let's say diamond as a higher chance if seeing it and you mine the diamond ore block but around the block is the ore golem. where it has similar looks of a diamond ore block. Sometimes the ore golem may stay as it's block morph but, sometimes if you're unlucky, it will turn into a moving mob and attack you. There is a low/ high chance the golem may take an item in your inventory whether it's a dirt block or diamond sword. Once it takes an item away it will hide like it was when you were breaking the ore. Since it's hiding you must find it, it looks the same block design as when it's watching for people who mine bores. If you find the golem successfully, you get your item back and possibly the type of ore the golem was (diamond, gold, and iron). The golem can be tamed but it is a very low chance (but possible). You may add whatever design or sounds the golem is/it creates. I just hope you take a look at this idea :)
Thank you for your time,