Well Natural Magic is based a lot on magic and adventure. There are many large mods in the modpack such as Thaumcraft, Botania, and Ars Magica 2. The mod pack itself is by WTFGeeks. Also in this mod pack, there are loads of different dimensions to explore such as The Twilight Forest. There are also many bosses to defeat along the way. I would highly recommend playing this mod with friends.
Karma is more of a tech mod pack. It combines both adventure and tech. The mod pack is by Chaoschunk. This mod pack focuses more on tech than exploration but exploring is defiantly a large part of this mod pack. This mod pack would also be a great mod pack to play with other people.
If you need me to define the mod packs more let me know, i was trying to be brief with my descriptions.
