Sorry to hear your character's demise, Aleastr. Was there anything in the planar sphere you actually needed? Because if SCS and solo, I would have been tempted to skip it. Best of luck in your next attempt.
Personally, I wouldn't want to miss out on the Ring of the Ram or Staff of Fire for a solo F/T.
And once again, I see Grond has completed an entire run in less time than between my updates...
Eryx the blade and party continued:
After defeating Tahazzar they returned to the dead magic room (through the portal we came), then Eryx - ignoring Yakman's journal in favour of the metagaming voices only he could hear - went south, to a room full of Alu-fiends, good thing I didn't throw away those charm protection helmets. Then south again to make a deal with a rhyming devil. South again to a room with two glabrezu summoners. From here the party buffs well and travels west to the room with a tree, then immediately North through the portal we came out of (this was to avoid fighting the demon knights and the wraith spellcaster back-to-back, not good at these levels and without a safe place to rest).

I managed to set off the damn Wail of the Banshee trap, I think my character's warped into the room right on top of it... PC had Death Ward ofc, but the sorcerer Randolph was lucky to make his save here. Aleks also got silenced by another trap (had to run him over it so the entire party wasn't debuffed by remove magic)
Fought the slave wraiths, the alternative seems to be running around a room full of traps to avoid them until their master is defeated.
The demon wraith herself is highly resistant to physical attacks, the best way to destroy her is with magic damage (Ring of the Ram, Holy Smite and MM) after sorc uses a scroll of pierce shield to bring her MR and protections down. I was pleased to find a Spell Shield scroll in this room.
Now, on to end of the maze and a game of cards with a demon before retiring (for those who don't know, it IS safe to rest in this cave).
This cambion is cheating though (no Spectral Brand for us this game...), Eryx calls shennanigans and another battle starts.

Things don't look so bad at first, though 3 of the party get their buffs dispelled immediately, used an oil of speed for Aragrish here (few things in this game are as frustrating as layering protection spells on a character only to see them all vanish with a wave of an enemy mage's hand). Aesgareth and his mage both had wilting in their initial contingency, fortunately no vulnerable characters were close enough. Two Greater Command spells from Leksa and Aleks knocked out the tiefling thiefling while Artemisia with called shot + Kuo bolts stunned their fighter immediately.
Killing the fell cats was a priority as SCS gives them the ability to lower fire resistance on hit; this is very bad with enemy mages around who are quite likely to have triple Flame Arrow sequencers up their sleeves, fortunately the cats were distracted by summons and only Aragrish took a hit.
My Remove Magic failed to dispel any of Aesgareth's buffs but it did wake up the tiefling backstabber, who I had somehow forgotten about in the past six seconds...

The enemy cleric managed to cast an uninterruptible Summon Deva spell, the wizard chain cast 2x time stop, spellstrike on Eryx (my Spell Shield was already gone) and several wiltings which were luckily spread out around the party. At least we'd chopped up their thief before he turned invisible again.

Now things are getting problematic, I've got three enemies who can breach or dispel me (the Deva, Mage and Aesgareth) and no spell protections.
I rebuffed Aleks, with Boon of Lathander & Improved Haste to slay the Deva, oh joy, another remove magic from that mage.

Not content with dispelling and wilting the party, the very annoying mage zapped Aragrish with a triple Chain Lighting trigger, he's on 1/3rd hp here after taking one of those superior healing potions, and just about to be hit by energy blades... Very close thing.

I'll say this much for fallen Devas, at least I get xp for killing them, unlike enemy summoned demons. Fortunately the Deva attacked Aleks, who has a good AC especially against crushing with the girdle of bluntness and pro evil from the sensate amulet, he was luck to save against the Deva's Chaos (they cast instantly, like demons in my games), also the party was lucky the Deva's next spell was heal on self... Globe of Blades could be nasty against our mid game saving throws. Called shot worked well to weaken both the Deva and Aesgareth when he wandered over. His mage was delayed for one round casting Death Spell on a fire elemental from the staff, after slaying Aesgareth we just ran past that mage and rebuffed a little in the room beyond the portal (I try to avoid this kind of thing, because enemies protections just wear off in the meanwhile, but that mage had proven herself to be quite formidable). Got a robe of the Good Archmagi from that mage when we finally took her down, and some useful potions (magic protection, clarity, super healing) from the other tieflings. Finally we can leave this maze!
Met Carston, annoyed him enough to summon four mind flayers, who were dispatched with ease, even with buffs running low. Further on, party finds some Yuan-ti, and where there's Yuan-Ti, there's Yuan-Ti mages! Even this late in the game I'm not going to risk it against them without buffs, so escaped the level for now.
Returning the next day, the Yuan-Ti are mopped up with ease, as are the Githyanki - I wasted my time buffing with spell protections, their mages are apparently really low leveled and with no anti-magic spells. It's a pretty easy fight even though they swarm you all at once (typical behaviour with SCS), the only ones to watch out for are the anti-paladins - in my game their Unholy Reaver swords can dispel on hit like Carsomyr - they were handled with called shot, Holy word and Greater Command.
Mind flayers were easy too, fewer of them here than in the sewers hideout.
Minotaurs - even super minotaurs - were also easy, got Axe of the Unyielding for Aragrish.
Carston cringes as his case crumbles, and the party finally gets to play with the machine of Lum, getting +1 strength for Aragrish, +1 dex & cha for Eryx, +1 con for Artemisia, +1 wis for Randolph.
Haven't fought demi-lich or Saladrex, I doubt I will... Saladrex - like Vithal - usually survives my games even if it would be more profitable to attack him. Some of the final level of WK will be left for ToB, as certain encounters there would be a bit much even for this party without HLA's (I have a personal rule about not wasting time in WK during chapter 6).
Returning to Athkatla, forge white dragon armor and upgrade the thieves' hood, quiver of plenty and golem manual (as I say, it's either that or leave the components cluttering my inventory till ToB). I guess that concludes our search for supplies, time to return to Aran and set sail!
Party is now in Brynnlaw, current levels:
Eryx, blade 20
Aleks, priest of Lathander 11 -> fighter 14
Randolph, sorcerer 16 (chose Horrid Wilting as first 8th level spell)
Leksa, swashbuckler 10 -> cleric 17
Artemisia, archer 15
Aragrish the Cliched, barbarian 17
Still no deaths, fingers crossed...