If you are wanting more detailed information and specifics on mobs or bosses, we have a well detailed wiki!

Bosses

• 9 Bosses with unique animations and attack patterns, providing a unique challenge to your survival world. Some of the Bosses are the Night Lich and the Void Blossom.
• 3 Mini-Bosses found in two of the dungeons. More to come later!
• 21 Mobs for the new dungeons, all having unique attack patterns and adding a lot to the dungeon delving experience!

Items (Use JEI for crafting recipes)

• Many utility items to help aid you in your progression.
• A new bow that is very durable and deals more damage and uses a specific arrow type.
• Many weapons all with there pros and cons, most of them having abilities or two abilities.
• 6 new shields with 3D models!
• Many  armor sets, most of them being head pieces or specific parts, the armor in this mod has unique properties such as full set bonuses or buffs they supply when a condition is met.
• 6 new food items giving various buffs, as well as Glow Berries are added in!
• A whole bundle of trinkets, they'll add boosts or new abilities to your character, adding different bonuses and further building your style. Has compatibility with Baubles!
• Locator Items for each of the dungeons, allowing you to easily find them in survival.
• Several Mob Drops, Boss Drops and crafting items that allow for a true RPG experience.

Blocks

• Many utility blocks such as the Levitation Altar.
• Moss Blocks/Vines/Leaves that can be found in the Rotten Hold or Void Blossom Cave.
• Multiple new entire sets of building blocks to spice up your builds!

Structures

• Rotten Hold, an early game dungeon for Iron equipment with a balanced take on progression
• Void Blossom Structure, you can locate it by looking for a pillar on the surface covered in mossy Stone Bricks and Lush Blocks or using a Void lily
• Burning Flame Arena, a new Nether Dungeon housing Aberrants and the Burning Knight of Flame
• The Night Lich's Tower, now has biome variants to them and is where the Night Lich can be fought at
• Frozen Castle, specific to snowy biomes, this labrynth underneath the ground holds many secrets and unique items to be crafted and gained.
• High Court City, a big broken city located in the sky harboring the hardest and final boss of the mod.
• Forgotten Temple, a long lost temple found in the desert housing puzzles and one unique boss encounter.
• Gaelon Sanctuary, a underground solitude of a fortress being a farmable location for materials that repair any armor or weapon from the mod. Also has many replayability features.
• Obsidilith's Arena, found in the End. This dungeon brings a new spin on the fight with Obsidilith, best to not under estimate this one!
• Mysterious Trader Post, a new villager type that when given the mod's mob drops will exchange it for other materials. Or you can give him Trader Coins that have the chance of giving you trinkets in return.

Other

• Several Config Options for Structure weight, Spawn Rate, Mob Configuration, and many many more. 
• Events such as getting certain achievements will have new mobs spawning in the world naturally or certain items being obtainable. Progression is key!
• Boss Scaling, per player nearby health and attack damage will be increased! Adjustable in the config.
• (WIP) Locate command for all structures except the Rotten Hold, type in console /locateDA "tab"
• Boss Enragement System - Bosses attack damage will increase when below 15% Health
• Boss Re-summoning - Bosses now spawn a block after they are defeated, by using a Soul Key you'll be able to re-summon that boss with slightly higher health and attack damage. This Re-summon system can only be used 3 times before fully disappearing.
• Boss Music - When experimental features are enabled in general_config. Boss music will be played for every single boss encounter. Just take in mind that the music is copyright until a composer is hired for this project.