yaAAALLLL I THINK I MADE AN INESCAPABLE MINECRAFT PRISON????
I haven't made it in game since I'm on holiday but I think I actually might have cracked it. Building it as soon as I can when I get back.
Anyways, here is Selene's Vault
The guards are all armed with silk touch netherite pickaxes, as well as swords and potions.
The prison itself is glass. The guards can see everything. Even if you crouch, you can be seen. You can't glitch or chorus fruit out, because it's sealed in a large empty space by decorated walls, and on the actual bottom of the place are trapped pressure plates.
You go through four item checks (set spawn, kill, collect items, continue), before descending a very long tower. The top part of the tower is removed via silk touch pickaxes when not in use, so you can't access it.
You set your spawn once more before you descend a one block water tube of obsidian into an end portal, one guard in front of you, one guard behind you. There's another guard at the portal, who can reactivate/deactivate the portal by controlling it's ender pearls.
You are then transported to the end, in a room sealed off by obsidian. There is a layer of water, another layer of obsidian, and a layer of lava surrounding the room. The guards take you down a tunnel and onto a stop, just before the void.
The guards then make and activate a flying barrage which transports you to the actual compound, a glass tube with three other tubes hanging below it. The flying barrage is deconstructed and placed back in the guards inventory. You are sent down a water stream to one of the cells that dangle.
The water tube is then cut off and you are alone in a small glass box. You can't break it for blocks to build up, since it's glass. You can't jump, because then you'll die and respawn in the main Overworld compound. Your just sat there. In a glass box.
Food and books and other things are sent down occasionally, heavily armed guards manning it. You can't do anything with them. Because you're in a glass box floating above the void and you can't reuse the blocks.
The second glass cube that is between both cells is a guard/visitor room, where they can both see and talk to you. The only difference is that they can get out and you can't.
At the end of your sentence, a water stream is tunneled down and you are transported back to the main end island via flying barrage and back to the Overworld, where guards will take you to a different exit, and let you free.
Crappy doodle with even crappier handwriting here:
Common escape methods:
Enderpearl glitching or chorus fruiting = all guards are armed with bows, you have all items removed four different times, and there's a good chance that chorus fruiting or ender pearl glitching will send you into the void.
Reusing blocks = It's glass and will break. The guards have silk touch pickaxes, but you won't unless a visitor manages to smuggle you one in,,, which probably isn't possible given the insane security levels. Visitors have to surrender their items and be checked four times as well.
Breaking and malfunctioning Redstone = There's almost not Redstone to malfunction, unless you count the flying barrages or the traps at the bottom of the main compound
Breaking lights like glowstone, sea lantern or shroom lights, and then crafting the drops into blocks and using them too escape = there are no actual block lights, only two lanterns in the cell.
Bed glitching = Can't sleep in the End.
Cell items = There is a lectern, a bookcase, a cauldron, a lantern and a chair. You need at least thirty two blocks to reach the top glass tube.
Friends = There are 128 end portals in an average world an I am far too pathetic and lazy to remove them. However, there are at least four netherite decked guards in the tube at a time, and several more in the compound and even if you do go through the end portal, you will spawn back at the main compound and will likely be transported back to the tube again. A small army might be able to get through though.
At the end of the day, I think that Selene's Vault is inescapable alone, and I will build it in the future to test it out. Your welcome to try and test it out yourself though!