Hematite

The design of the modpack takes cues from Vanilla, but does not limit itself to being "Vanilla-plus." 

There is a wealth of dangerous mobs which stalk the world throughout both day and night (LUMINOUS, Born in Chaos, Undead Unleashed, etc.) and relatively few easy options to stop them, so expect many deaths, particularly in the early game. The best weapons in your arsenal are the minimap, JEI, and the roll button. It might as well be impossible without them.

Most progression is exploration-based (Nameless Trinkets, Relics, Celestial Artifacts, etc.), although the mainline of the mod runs through Terramity progression. There is also Create and Mahou Tsukai to appeal  to alternative playstyles. 

There is no new dimensions; instead, the existing three dimensions have been "remastered" (Geophillic, Jaden's Nether Expansion, Eldritch End, etc.). Alex's Caves is also present.

Good luck!