Cataclysmic Apocalypse

This was created as a collection of mods that add various bosses, weapons, and ores to the game and contains mods such as cataclysm (the main one), mutant mobs, origins, and a bunch of other random things to make the game harder. (It's really just for me to play cataclysm with a few friends but with a little extra flair added in, but by all means if other people want to play it, then why not?). The mods add tons of new mobs and biomes, and new weapons and armor to fight these new bosses with. There are quality of life changes such as the ability to see how much hunger and saturation is restored thanks to the appleskin mod. A personal favorite of mine - Xaero's minimap and world map are included so that you can see where you've been, where you are, and the mobs and landscape around you. JEI lets you review the new items and recipes to make it easier for you to find and craft new modded items. When you first start the world you can choose your origin, which gives you a multitude of ability's that can help or hinder you for the rest of the game, from the origins mod. Your main goal will be to defeat all of the bosses from the Cataclysm mod, as this is what the modpack is based around. To do this you will have to explore your world, searching for boss dungeons and most likely running into plenty of difficult mobs along the way. 

DISCLAIMER: I have not created any of the mods myself, and highly recommend checking out the actual creators, because these mods are super awesome, and I'd like them to get the credit they deserve for creating these incredible mods.