Nycx

Nycx is a dimension that looks similar to the Nether. The dimension is mostly made from obsidians and Raw Onyx blocks. Raw Onyx is a common block that you can find here, you can smelt it into an Onyx Nugget and use it to craft Onyx gem and use them to craft tools. The tools are not too strong, but it's very durable.

Lava seas can be found here, even lavafalls can be found here. Lavafall is a phenomena where a huge amount of lava falls through a vertical landscape. The entire dimension is filled with lavas and there are cracks here, the cracks are filled with lavas too, like magma blocks.

The dimension is filled with only neutral and hostile mobs, they are all monsters. Nycxian is an extremely hostile monster that can be found here, it is very common and they are all equipped with an Onyx Axe, the Onyx Axe does the same damage as a stone axe but is more durable.

The Nyctomancer is a type of illager that can spawn here, it is capable of summoning Nycxians and Dark Souls, it is very resistant to damage and is immune to fire. Dark Soul is a hostile mob that can be found roaming around in the Nycx dimension, it can pass through blocks and can fly too.

It's hard to survive here due to the lack of food sources and resources. The place is also too dangerous so it's unhabitable. If you want to live here then you will need to bring some animals here and farm them here to get some good foods, water can still be placed here so you can grow some crops.

To enter the dimension, make a horizontal square frame, it must be 5 by 5 blocks, then you will need to put lava inside that frame and the portal will open. Enter the portal and you will be sent into the Nycx dimension.