There used to be legends. Legends of places below the previously conceived bottom of the Overworld. Some said that the Bedrock was the end of the line, while others said that it was just a barrier protecting us from what lies below. -DesinitDraco

Temporary edit until I put out a proper fix:

Here is Wozat's hotfix for the update check crash bug: Link Removed: http://www.mediafire.com/file/5ljt0cnrvo3bqfg/DeeperCaves-1.0.0w-mc1.7.10.jar

Ever wanted to explore below the Bedrock? Do pits 200 blocks deep, mazes of caverns, and compressed ores sound interesting to you? If so, you may want to take a look at this mod!

This mod is based on the Deeper Caves suggestion by kittykattykat here: http://www.minecraftforum.net/forums/minecraft-discussion/suggestions/2311624-deeper-caves-caves-going-more-than-2-kilometers

At this point, there are Drop, Maze, Crystal, Compressed, Bedrock Plains, Near Nether, Near Void, Deep World, Darkness, Abandoned Caves, Far Void, Evil, and Final Labyrinth levels. All ore blocks on those levels have been added. However, Ametrine also does not have the mob-attracting effect.

Source is at: https://github.com/valiec/deepercaves

Discord: https://discord.gg/g9u4QEhfa7