This is Fanon and thus isn’t in the game. Also, it is a literal Minecraft reference. The picture is from the Minecraft Gamepedia for “end portal”, all other images are from the wiki. Please behave yourselves.
The End Portal is located in the End Times Biome, which has a 30% chance of spawning instead of a Phantom Tree. Instead of Eyes of Ender, it uses Preserved Flamingo Eyes instead. The Portal will always have at least 6 eyes filled in already.
A special “rotten eye” which is a brown variant of the Flamingo Eye may spawn, which cannot be used to travel to the End. It can be replaced with a fresh one however.
Crafter’s Hat may occasionally be present, and can be used against him later.
The End itself is a hellish dimension, set on several fragments of each Biome present in Lumberland. A larger, grey colored island is in the middle. Oftentimes dead tree fragments will fall in and form Phantom Trees. Several of what appears to be destroyed player bases will be present, and often include Worklights, Utility Vehicles, and broken sawmills. A random axe has chance of spawning. A single large Phantom Tree will spawn in the middle of the grey colored island.
The Boss Battle
If you cut the tree in the middle of the island, the smaller islands will crumble away and fall, and the cut tree will die. It will remain quiet for up to 10 minutes, giving you some time to prepare yourself for the imminent attack. After 10 minutes or less, Crafter will suddenly appear, shotgun in hand, ready to take you on.
He will exhibit similar behavior to when a player is robbing him, by chasing you and shooting you. He can easily be cheesed via literally hiding in behind a cheese shaped and textured rock. Crafter will then calm down and start walking around, giving you time to heal. He receives more damage if you wear any variant of the International Fedora.
Once Crafter is at very low health(a red bar), he will summon the various other NPCs from Lumberland to assist him.
Thom and Ruhven will first appear, Thom will throw various axes that are sold at Wood R Us while vomiting out the green acid like liquid from the Wood Dropoff and Sawmills that can do damage over time. Ruhven will throw Land Signs at you while screaming in all caps.
Jenny will appear and will roll tires at you. The tires do a small amount of damage while pushing you around and making you fall down. She will then drop various cars that knock you down and take 25 health away from you.
Finally, Corey will appear, and he will rain down hundreds of Lightbulbs on you with a gun shaped refrigerator. Each Lightbulb will do 1 damage, but it will have a lot of knockback. He will take breaks to reload. He can also throw balls which deal massive explosive damage.
If the player dies at any point, Bob will show up and revive them with a can of worms. The player will then respawn and Bob will give some Dynamite to help. Note that this can only occur once, to prevent amassing of dynamite.
After defeating all the NPC’s, Crafter will come back with his health bar in the yellow. If he gets hit, it goes down into red again, he will then enter an enraged mode and use all the previous NPC attacks and his shotgun. Once killed, he will explode and then start pouring out various items, from expired presents to boxed axes that are no longer for sale, and even bits of wood. After he is done with pouring out his loot, a boxed Golden Axe will descend from the sky.
This battle can only be done once per save slot to prevent spam-killing the boss to farm large amounts of items and the golden axe. If you go back to the End after the boss fight, it will simply be a old arcade machine with a list of everyone who also done the boss fight in the middle of the island.