Large hollow hills are one of the few places that can still challenge a late-game player. In maximally enchanted thaumium armor wielding a fully enchanted Sword of the Zephyr and Wand of Lightning, I still have to be very circumspect when I crack one of these open. It's very easy to get surrounded and overwhelmed. Quantum armor or the MPS equivalent makes them trivial, of course, but what isn't that true for? The rewards are worth it, though, at least in the early-to-mid-game.
I recomend this for hollow hills (or caving in gernal)
Shoops basic survival bag of tricks
- Bring graval, sand, or at lest dirt. Torches. and Food (yeah dont really need to say that)
- Light up areas as you go. I do about a 30x30 area at a time
- Block off areas to make choke points while you work
- Seal finished areas off and mark them somehow (I like to do this litle T with blocks)
With this is does not matter of the whole wolrd spawns outside your work space. you can just murder and move your choke point foward as needed.
Another thing I suggest if you got the resources is building an endechest/bag system to give you basicly unlimited invtory. Bouns you can use a manger to keep it stocked with torchs, food, and tools while still pulling out everythign else you stuff in the enderbag.