Previous to Terraria version 1.2.4.x it would have been bad to mine out a lot, because the only way to get hardmode ores was hammering these demon altars and creating new ores. Those where made by morphing existing blocks randomly - and if the RNG decided to morph a lot of "air", fewer ores where generated.

Well, I just happened to exit the map after defeating the WoF and collecting the loot, when the game stated "setting hard mode" (saving screen) without continuing. I closed the game and loaded it again, just to find my world as it was before - despite the map showing the two transformed stripes of hallow and crimson. But once one travels there, there is no other biome than before. xD

Edit: Seems like hardmode doesn't trigger correctly in this world. >.> Will try the next character then.

Edit: Doesn't work. I wonder why?

I got the "Still Hungry" achievement but not the "It's Hard!" one - so hardmode didn't trigger at all. If I play on after defeating the WoF there are in fact Crimson and Hallow biomes, but the game doesn't save the map.

Opened a couple hundred more crates yesterday. You tend to get a lot of repetition on the accessories and weapons, but at least they sell for a fair bit of coin. But I don't really need 8 Falcon Blades or 6 of those time-jump doohickeys. I did get a few different types of Souls, so that's helpful. I'm now down to 99 each of Iron and Wooden Crates. Until I can crack the Wyvern nut, no more Sky Lake fishing for me.

Had plenty of bars to make a set of Titanium armor. Still getting my butt kicked a fair amount, but that's likely because I'm still operating with the pre-hardmode mindset where I wasn't being threatened much. For certain, it doesn't take many 60+ hits to quickly find oneself in trouble.

Also made a Titanium Trident, for help with the Wyvern. In case you can't tell, killing that thing is my next goal. ; ) Well, that and clearing out and blocking off more Corruption and Hallow.

Noticed that the ceiling for Harpy spawns has been lowered quite a bit - I'm now encountering them at the higher ground elevations instead of only seeing them at my sky bridge. As I recall, that was how I first encountered the Wyvern, too: was running around one of the tallest peaks and it spawned when I jumped fairly high while in combat.

Sounds like there's some issue with your save files, either the directory or the world file itself.

Do other changes (like building a new room) to the world save?

If I don't defeat the WoF in the run, everything I do is saved, but if I do defeat it, the save screen freezes (character is saved, but not the world) with the prompt "setting hard mode". And I also don't get the message "The Ancient Spirits of Light and Dark Have Been Released" upon the death of the WoF. So, the script for hardmode doesn't trigger correctly, I assume.

I created a new world yesterday, dug to the underworld immediately and killed the WoF - everything went fine in that world, and I also got the "It's Hard!" achievement as well. Went back to the previous world and still no reaction, save screen freeze ect.

You can try it yourself, if you want. There's a link for the world file: via Zippyshare.

If I had to name a plausible cause, it would be the usage of a Beta version of TEdit to remove the water that I was to lazy to collect by buckets. Maybe that corrupted the file. But the world works fine any other way.

That does sound likely. Even though TEdit is mostly safe, I do not find it hard to believe that messing around with liquids could cause some kind of corruption of the world file.

Found a couple Nimbus Rods. Interesting weapon, allowing one to set portable 'traps'. Used it a bit last night while exploring the Jungle and Hallows areas on my map, and found it particularly effective against creatures that like to move back and forth a lot - the rain was taking out a lot of hornets and other flyers while I was tucked behind a low wall with my newly-acquired Amarok yoyo.

So I'm thinking those rain clouds will create a sort of damage-inducing arena of sorts, perfect for helping with the Wyvern. I imagine the rain will also do a number on bosses, as their large size means they'll be under a cloud for a fair amount of time and taking multiple hits. Gonna play around with it a bit more to see what works best, how far the rain falls, how placement works, optimal distance between the two clouds, etc., and then make an extension to my slum / residence where I can fight from flat terrain with the nurse nearby. Still not sure which weapon to use after the clouds are in place. While the Arkhalis delivers a lot of hits very quickly, the downsides are that you have to get really close and the damage it delivers is a bit low for Hardmode. Got a couple large-arc swords that might be okay but I'm spoiled by the 360-degree action and wall-of-damage from the Arkhalis. Might use the Magic Dagger but I also need to play with that a bit to see how well it will work.

Update edit:

Nimbus clouds did the trick. Used the yoyo a little bit but the rain clouds must have done 90% of the work. Maybe 20 seconds of jumping around and that was that.

Now, going to try one of the mechanical bosses with similar tactics.

A few things make this less likely to succeed on the first couple of tries:

1) They have noticably more health than Wyverns.

2) They have more ways to deal damage than Wyverns do.

3) You have a time limit to defeat them (until dawn).

Not that it would be impossible to do it they way you killed a Wyvern, just don't expect it to work quite as well.

So, any other (relative) Terraria newbies finding any nice Halloween "treats" in-game? I've already found more than a dozen (I'm guessing) goodie bags since the 20th of October when the Halloween in-game event starts -- all in no more than 6 or 7 play sessions, and without particularly trying (not doing anything much different from my usual semi-random exploration/wandering, anyway). I got the vampire costume, robot costume, "Bride of Frankenstein" costume, two or three (identical) blue ninja turtle costumes, a fox costume...and there might be others. I also finally bought a sickle (I'm still playing 1.2.4.1, in which one can only buy a sickle from the merchant during Halloweentime), found a machete-thing that functions as a boomerang, got a black cat pet (which, sadly, doesn't seem to have any game effect -- it certainly doesn't attack anything), and have stockpiled dozens of rotten eggs (also from goodie bags).

haha - it didn't work well. At all. I'll need to work on getting better weapons before I try that again.

There is a decent amount of non-combat/vanity pets, one of the alternate gear slots (1.3 UI) is specifically for these. The Black Cat is the cutest of them.

The way I (finally) beat the Destroyer was:
* I found an ice sickle in the snowy underground region which really helped, as it shoots piercing missiles which hover in one spot
* Set up a little "destroyer house" away from my main house, about 30x20 squares to keep most of the little flying droids out
* Inside the house I put a campfire and a heart lantern to help with healing
* Made some strong healing potions as well and had some nice accessories to raise the invulnerability period after getting hit
* The main battle tactic was to stand in the centre of my house and then when the destroyer pounced, move slightly aside and then fire a bunch of ice sickles at it. That way I avoided as much damage as possible but it was still easy to cause lots of damage.
* From memory, the Golden Shower was also helpful to lower the Destroyers damage resistance

After beating it the rest were much easier, as I was then able to make a MegaShark which works great against most of the other bosses.

Just underwent one of the rites of passage of this game: accidentally summoning the Wall of Flesh. If I had been moderately prepared for it, I might have even been able to kill it, but the question is rendered moot by the fact that I haven't even decided yet if I want to go to Hardmode in that world. It's my oldest world (I only have two), and -- with the exception of having too many meteor-impact sites marring the landscape -- I rather like it as it is. If I do feel like trying Hardmode at some point, I might just create a new world and use it with my existing main character, running through all the prerequisites quickly and not worrying about getting things "the way I like them".

In retrospect, I probably should've just committed lava suicide or tried to use the magic mirror (same effect ;) ) as soon as the Guide died, but I figured I'd see how long I could stay alive. I actually lasted at least a couple minutes, but I finally ran out of easily navigable dungeon (hit a dead end in one of the underworld apartment buildings :) ).

I seriously think that's how EVERYONE first experiences the Wall. :P

2nd or 3rd time I got to him I finally killed him, and surprisingly easily. Of course, the 2nd or 3rd time wasn't on accident so I was ready for that bastard! :D

BTW do you have moose where you live, because I do, and they find your avatar a little trite. :P

Then immediately after defeating it, you abandoned the world because Hardmode? =P

Aside from me? Nah, mostly just deer. Most moose tend to prefer a wee bit more foliage than you generally find out this way.

EDITED because "world" is supposed to have the letter "r" in it. =P