Looking for bit more of a challenge? Inspired by the amazing End Remastered, this mod makes it more of a challenge to enter The Nether. No longer can you simply just obtain some obsidian, craft a flint & steel, activate portal and stroll on into The Nether. You can still craft and activate the portal however you will no longer be able to enter the dimension.
To be able to enter The Nether you must defeat a number of enemies to obtain Mysterious Shards, Nether Essence and the most challenging of all, the Nether Crystal. Obtaining all these items will allow you to craft The Seal Of The Underworld, consuming this seal will deem you worthy of entering The Nether and will then allow you to enter the portal.
How to obtain Nether Essence, Mysterious Shards and Nether Crystal
Simple and nice.