It is recommended that you begin mining straight away. The first ore you should focus on is iron. You will likely engage in combat more often and more intensely than in vanilla Minecraft, so having iron armor at the least is very important. Remember that coal is not an issue because it is very easy to create charcoal due to the Treecapitator mod. Gold is optional, but recommended, because Werewolves are extremely hard to kill without a golden sword, but can be quite rewarding, dropping Golden Apples and tools. You do not have to worry too much about diamonds because other materials are stronger and you have an unbreakable Soul Sword that can become far stronger than diamond. Of course, if you do find diamonds, go ahead and mine them. Thaumium is one such material, and it can be most easily found in the dungeons created by the Better Dungeons mod. These dungeons are not easy to defeat, however, so keep your wits about you and bring good equipment.
The Better Dungeons Mod adds many kinds of dungeons containing tons of loot. However, most also have even more dangerous creatures, so strong equipment is a must. Both Millenaire and vanilla villages will spawn as well, and you'll have to use your feet to find them. Pressing the N key will tell you where the closest Millenaire villages are, but you must load the chunks containing them at least once before you can find them, and there is currently no easy way of locating vanilla villages (In some versions it is the V key). A fair bit of exploring should help you locate Silverwood and Greatwood trees as well. Be careful though; getting lost at night could prove deadly, and though you won't lose your items, you will lose all your experience and you will respawn back at your bed.
If you have any questions, simply explore this wiki!
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