Elemental Gollum Minibosses

I think some new dimension specific mini bosses would be really cool, something you can build and bring to life similar to the wither or iron/copper gollum; say you defeat the overworld, nether, end, & sift gollum mini boss fights you could be able to put all their unique drops together to create a cool magical weapon or a unique upgrade; this would bring way more incentive to visit & explore every dimension, all while being fun and making sense with the other gollum mobs in the game.