Endermen

Endermen are the most intelligent species in The End as part of Resolution/The Dragon's thinly-threaded hivemind. As babies, Endermen have no antlers(?) and have to grow into their hands. Their growing period is somewhat awkward and unpleasant, as their legs stay short and mostly unhelpful until they reach adolescence.

Endermites

Endermites are an invasive species and a very short-living mini beast. They seek a grounding substance to consume so that they don't die so quickly. The oily substance inside of enderpearls could do this for them, which results in resting pearls being destroyed by large groups of mites for a good meal. The bottom of Endermites is a soft and breakable material, while their body and head(?) shells are both nearly as hard as a shulker's shell.

Shulkers

You know what the end reminds me of, more than anything else? An ocean. Or more accurately, an ocean where all the water suddenly vanished, leaving nothing but void.

There's a post somewhere on this site theorizing that endstone is coral skeletons, and I liked that post but I think it didn't go deep enough.

Like, look at End Ships. They look like boats, like the shipwrecks you can find in the main game. Even chorus plants invoke an ocean like feel with how they grow. It's like an ocean where the water disappeared. The bedrock vanished, and the water just drained away. Leaving behind the very few species that could survive without it. Inviting in a species that thrived without it.

As for Shulkers, we actually have an answer for them! They're City Golems! That's what they're called in the game files, and it actually makes a lot of sense when you think about it. Shulkers will attack any mob in range, including other shulkers. Endermen are immune on account of teleporting away from projectiles, but anything else is in danger.

The reason you only find them at End Cities is because they aren't natural mobs. Someone put them there as guards. You can even dye them different colors in bedrock. They're little defense turrets!

The real question about shulkers for me is why were they built? What were the people who came before you trying to keep away? Why weren't iron golems enough?

There's three mobs found naturally in the end: Ender Dragons, Endermen, and Shulkers. Both the Ender Dragon and Endermen are immune to Shulkers, so it can't be them.

Elytrin wings are a type of high-speed wing, they can fly fast for long periods of time; the end has long gaps between islands, which is why all end type hybrids have some type of traveling method. Enderians have teleporting, shulks can float, elytrisn can fly and dragons can...well also fly-

Oh! And rant here, nether hybrids are all immune to fire and heat, like they can bathe in lava. Unless their a tracer, in which case they just have a resistance to being burned(by the sun or heat)

The main layer of feathers, like the top, represents an elytrins over all personality or a key personality traits one might say; shekby ahs always been creative so purple was her color, false is more calm and a bit distrustful so a grayish blue fits

The primary/secondary feathers, the ones under the 1st layer, represents something their good at; Shelbys good at bringing people together so green, false is good at tinkering so a light copper color fit

The same goes for enderians but about their horns and tail fluff, respectively. So Olis horns are purple while his tail fluff is pink

The same goes for a dragons spikes and wing skin thing, and shulkers shell coating(top and bottem); nightlights would be a dark blue for his spikes and a deep purple for his wings

so for ur mob fusion au, i imagine that end mobs are really really hardcore bc theres not a lot to eat there. endermen would have it easier because they can go between dimensions, but shulkers and dragons don’t have that so they have very weird adaptations. by this, i mean that shulkers act like mollusks and dragons are a bit like snakes and crocodiles and bears.

shulkers filter feed, mostly eating the bits from chorus plants that fall off and drift around in the end’s dense water like atmosphere. sometimes endermites will try to hide in them, or tiny bits of endstone get into their shells, and they isolate it, making little balls that they spit out at predators.

(the further down you go, the denser the end’s atmosphere gets, allowing the end islands to float on top of the gas that makes up the end’s air, because the porous rock is much less dense than than it. its also why you die when you fall into it, you start suffocating because theres no oxygen.)

dragons on the other hand, are more active. they can eat and digest almost anything without any problems because their stomach acid is so strong. the things they cant digest are strange and unexpected; bedrock, water, clay, sponge, shulkers, endermen, ender pearls, and string. some of their favorite things are even weirder; obsidian, netherite, endermites, shulker bullets, blaze rods, lava, and sand.

so sometimes, a hermit will come across some strange end phenomena occuring in the overworld, curtesy of grian, mumbo, Ex, and X.

like Ex and X arguing over how close is too close to be standing when it comes it family dinners.

or both of them standing stalk still, in separate chunks in an overworld or nether biome, making off-hand comments about the quality and nutritional value of the food, despite there literally being nothing else around but them.

like grian boldly pestering Ex or X for “star candies” every so often and them complaining playfully about how “you’ll have to wait a week or two, they take time”, and mumbo shyly asking for a few.

like mumbo running from an endermite and jumping behind someone, while grian just picks it up and swallows it whole.

like finding grian happily chewing on nether portals from time to time, without ever explaining.

like grian asking zed for one (1) of his blaze rods every month, and zed being somewhat freaked put but mostly confused because why does grian know exactly how long it takes him to regenerate a blaze rod?

if nothing else, the end folk know how to work sustainably, because the end is rather bare of resources. they never ask for more than they want or need because they are so used to working within the end’s limits.