Hammers smash background walls.
of note for anyone new.
In order to smash background walls underground, you need to have a "path" from open air. You can't just smash it out randomly.
However, when you PLACE background walls underground, you simply place your walls OVER the rock/whatever background.
Also, I wasted alot of time trying to figure out how to make grass/moss/leaf backgrounds grow in 1.2. don't bother. Dryad sells them at 10copper each.
Brikker, you have several goals atm.
gold or platinum pickaxe and armor. (one or the other will have spawned for you.)
hook
town. like 10 rooms for npcs. seriously there are alot of them now.
collect over 200 life. This will cause Eye of Cthulu to start spawning at night. This will give you crimate ore, or shadow ore. for the next teir of weapons.
Alternatively, go find the Jungle. Explore this for better gear.
then, explore crimson or corruption.
At the base of either will be demon hearts or shadow orbs. Smash these with bombs. for nice loot.
And danger. smashing 1 will spawn a meteorite. you can back out, and go find this for meteorite gear.
Or smash 3. and spawn a new boss. This boss is the gateway to pre-hardmode end game. it will drop crimate or shadow ore, as well as the extra material needed to craft next teir pickaxe/armor.
which will allow collecting of everything pre-hardmode.
fighting bosses. won't get specific.
But a few very useful things for all of them.
1. potions. Ironskin potion is amazing and cheap. especially early game where it basically doubles your armor. regen is good too.
Campfires are super strong as well early. A large flat area is best. prepping an area in front of the dungeon(oldman/skeletron), or area in crimson/corruption for that boss is a very good idea. a good screen wide flat area. with some wooden platforms, so you can jump up and avoid attacks.
Ranged weapons are generally far better then melee. Flails, boomerangs, flame arrows. +archery potion.