Space realm

Use this to get get the helmet item eventually
/setblock ~ ~ ~ minecraft:chest{LootTable:"minecraft:chests/end_city_treasure"}
Also play on full brightness bc I didn't realise how dark it was when I was making it

1.16.4 You can get to the space realm by travelling to y level 300 in the overworld (elytra etc). However the air is thin and won’t be able to breath, find the hidden relic: the space helmet to survive in this environment. Travel to the end cities and you shall find it among their treasures. (Just look in a bunch of chests)

(also you can use silk touch on the embedded iron ore)

dev note- there may be some bugs resulting from the use of a incomplete custom block method, this datapack is more akin to a proof of concept