you could also possibly find an airship on the way out.
Dude dust off that table and expand it. You can use the wild Mythal effects table for Myth Drannor too if you have it. Also all the Wand of Wonder tables ever invented and regardless of edition.
To me the Halruaa of now (after I get done being mad at WotC for Teh Stupid they inflicted on that awesome nation) is like one giant Myth Drannor.
Were I you, I'd be sure to pit the players against adherents of Azuth who are trying to recover "lost artifacts" of Azuth's worship that are purported to hold the key to bringing him back. Just as well I'd have followers of Asmodeus there, just in case something turns up. ;) The Blue Flame peeps ought to be there too, just because.
Hells yeah the Wild Mythal Magic Table! I had forgotten about that one, yeah theres some real good ones in there!
And yeah I miss the Halruaa of old as well, but I guess it does make for an interesting adventure locale now, definitely one giant Myth Drannor, I do like the new Myth Drannor though, but thats probably partialy because in my own campaign, Myth Drannor ended up getting cleared out and rebuilt.
I didnt even think about followers of Azuth, or could use Mystra as well, they would probably get some kinda wiggy spellfire power like maybe being able to cast old school auto-hit magic missles and 20d6 damage fireball spells.
Oh man, Im gonna end up killing these guys!
Im planning on sending my group into the very heart of the Plagueland that was once the mighty Halruaa. Other than the obvious Spellscarred what would be some of the hazards? Should magic function normaly? Should I dust off the old Wild Magic table? Any ideas would be much appreciated.
I think it'd be appropriate for it to be a bit depressingly haunted with apparitions, but without being too gothic-y horror. I mean, what a tragedy, right? There was an article a short while back on living spells which was fairly unique flavor-wise but would probably be right at home here. Animate objects and mimics might be good too, with their classic, old magic feel.
Larakens are mentioned in the 3e FRCS...magic devouring demons or some such in the swamps. Those combined with the current breaches to the elemental planes spells a lot of demonic and elemental incursion.
I would doubt that magic would function completely normally, unless it was a cover for something sinister or dangerous of course. Perhaps normal spellcasting builds up to something bad happening...so to avoid that most spellcasting creatures in the area use X or Y weird method. X or Y method being something akin to wild magic, etc. Sarrukh, elite lizardfolk, and aboleths are mentioned as living (or scouting) here; maybe they know more, along with those crazy blue fire folks.
What might be cool is if you could play on old edition mechanics without totally screwing your players over. Perhaps all arcane encounter powers can only be used once, but the caster gets new encounter powers after a short rest by eating mutant toadstools that grow everywhere. Perhaps even non-arcane characters must do this.
Ties to Netheril could also be played up. If you don't want to use the Shades and friends themselves, perhaps keys to destroying Shade could be discovered. That's more of a plot than a hazard, but you could always put the info somewhere dangerous!
Back to eating and hazards, what will the PCs live on??????? If any resources do exist, maybe they are guarded by refugees. Arcane zombie refugees that fly and eat spells!
Or, you know, whatever. 
(Edit: Actually, arcane flying zombies sound pretty creepy cool to me.)The terrain could vary extremely and not make any sense at all. Perhaps instead of like the Elemental Chaos where sometimes one element dominates maybe a type or theme of magic dominates (without going all Thayan zulkirs, of course). Gravity might warp in some places, as might direction and distance.
Sheesh, who the heck wants to go to Halruaa???
To most observers, and those who pick over the burned earth in search of ruins and buried artifacts, Halruaa appears to be a wasteland where nothing survived. Why then has nothing been found? Was the devastation of the Spellplague so complete that not even the deepest underground ruins survived? Certainly, it would seem so. Random spellplague energy still roils across the burned landscape in many areas, making it mortally dangerous to explore. Additionally, plaguechanged aberrations haunt the realm, discouraging all but the most dedicated treasure hunters.
The truth of the matter is that although much of Halruaa was damaged by the spellplague, it survived. When Mystra died and the Weave disintegrated, many Halruaan cities were pushed into a phased reality that remains connected to Toril but existing somewhere "in-between" Abeir and Toril. Halruaan survivors became even more dependent on magic for their survival, as they lost ready access to food and other essentials once acquired through trade and from working the land. The cities remain in close contact with one another, but did not have the ability to breach the rift separating them from Toril until quite recently.
The first few Halruaan returnees to Toril were shocked by the devastation to their former lands, and horrified to learn that their patron goddess had been slain. Immediately they decided to remain hidden and isolated. With the expansion of Netheril, the danger of Sharrans, Cyricists or others learning of their existence, and the dark pall that had been cast over many societies in the Realms, all of these contributed to the necessity of keeping their survival secret. A few citizens have chosen to return to Toril, but all who do have agreed to protect their interests by remaining silent about Halruaa. Some simply wished to return to Toril and settle in peaceful cities, some have taken up adventuring, and others are agents of the Halruaan ruling council - sent to gather information on this "new" Toril and report back from time to time.
In the absence of Mystra and Azuth, many Halruaans have taken up worship of Selune. Shar, the goddess of secrets, has become aware that an unspoken secret has arisen - and to date, Selune has kept this secret not only from Shar but also all the other gods. Other Halruaans still cling to hope that Mystra has survived in some fashion, and an even smaller subset of her former faithful seek out a method to bring her back or turn back the clock. They may yet pierce Mystra's veil against time travel and find some way to prevent the Spellplague altogether - resulting in a radically different timeline.
Im planning on sending my group into the very heart of the Plagueland that was once the mighty Halruaa. Other than the obvious Spellscarred what would be some of the hazards? Should magic function normaly? Should I dust off the old Wild Magic table? Any ideas would be much appreciated.
Silver you might want to check out the Mournland from Eberron for ideas. Its the closest thing to the Mournland in the Realms IMNSHO.
Just a thought...
you will need to deal wit ht he halruaa consumtion disease while your there.
wonders if the disease immunity items are still around
Good ideas everybody! I like the Idea of a "phaze" Halruaa, I dont think i'll use that idea, I think it would be too helpful to the pcs, but It is an excellent idea and very probable with a nation of high magic.