I went around and started smashing altars. Think I got too carried away, though, because I smashed on that was really close to one of my bases... that would have been smart to keep. I have other worlds I can go to... but still.
I found some pixie dust, but since my base is at the dungeon entrance, buried in pretty good, I don't have any worries about creatures.
Also got luck and found a snow globe, no idea if there are any good drops from the snow legion, but I guess I'll find out.
If you have a Phaseblade, the first thing you should do is make a Phasesaber. If you don't just mine so Cobalt and then progress. Phasesaber is made with a Phaseblade and 25 (I think) crystal shards which are in the underground hallow and can be obtained by smashing them with a hammer.
A familiar note is produced. It's the note Desolation plays to keep its instrument in tune
Smash a bunch of Alters then go hunting for Cobalt and Crystal Shards. Basically do with the poster above said.
You can either just make the drill of each set and then go straight for Adamantite armor or just make the armor set for each mineral. You won't need to make new weapons until you can make the Hallowed gear as the Phaseblade will be sufficient.
The Phasesaber is the best sword in the game IMO. I know most people will disagree and say the Excalibur but the problem with it is you can't turn around while swinging it. Having said that if you can get 50 Crystal Shards and a Phaseblade you will have a great weapon to carry you through hardmode.
Sick liaisons raised this monumental mark The sun sets forever over Blackwater Park