Arcadia, Half-Elven Fighter/Mage: The Unseeing Eye
If you have a problem in life -if things aren't going your way- then this is my hope for you.
I hope there is a dwarf in another dimmension who cares. I hope there is a dwarf in another dimmension who will cry for you, weep for you. I hope there is a dwarf in another dimmension who will send you chocolate and pay your bills. I hope there is a dwarf in another dimmension for us all.
Amen.
Arcadia is pleased that she has a dwarf in another dimmension who cares for her. The beholders of Athkatala, not so much.
Ok: Some dos and don't for straight-up arcane beholder fighting without summons, the cloak, or the shield.
Do have a Spell Shield
Spell Shield will stop anti-magic ray without being dispelled itself. This is the only way to stop anti-magic ray. Without Spell Shield you have nothing (or you'll soon have nothing).

Do have 100% magic damage resistance, a Globe of Invulnerability, or Spell Immunity: Necromancy
The primary beholder damage stalk is Cause Serious Wounds, a level 4 Necromatic spell, which deals magic damage. My prefererd option here is 100% magic damage resistance via Protection from Magic Energy (L6). That will last one turn per level- far longer than the alternatives.

Do have 100% electricity resistance, a Globe of Invulnerablity, or Spell Immunity: Evocation
The secondary beholder damage stalk is Lightning Bolt, a level three Evocation spell, which is favored by Gauths. My preferred option here is Protection from Lightning (L5). Like Protection from Magic Energy, it will last one turn per level.
Do have substantially negative saves
The other stalks -including fear, death ray, paralyze, domination, charm, petrify, slow, and telekinesis- permit saves. Stop 'em cold.

Do run a pre-battle checklist
Be sure to visually confirm that all your defenses are in place before battle. If you've forgotten something, there won't be time for in combat counters: the rays are too fast.
Spell Shield: Check

Negative Saves: Check

Electricity and Magic Damage Resistance: Check

Do open with massive damage
Even if you have your defenses locked down, plan to nix your foes quick. This is more for your safety than your characters safety: seeing all those beholder rays can be stressful- even if you know your character is safe!

And finally a don't: Don't rely on Spell Deflection or Spell Turning
You can run Spell Turning at the begining of a battle for a little extra damage, but you should not count on Spell Turning or Spell Deflection for defense over an extended battle: they'll be consumed, and there have been reports of rays erroneously bypassing Spell Deflection.
Ok. With that out of the way, onto the quest.
EDIT: Ran out of time. This had to be fast. I'll try to flesh stuff out later.
The sewers crew furnish an opportunity for Arcadia to test her game plan: buff-> Skull Trap x 3 Sequencer -> Ages
And how did it work?
Disco.


The most challenging battle of the quest was actually not a beholder fight: it was a random spawn mess that I stumbled into. I had planned to stealth by the yuan-ti crew that I expected to see down there, mostly because I didn't want to buff. But when I saw just these undead -and nothing else- I decided to fight.
(And yes: In this shot, Arcadia is still fighting ghasts BG1 style, with the sling)

That would have been fine, but then Arcadia heard a noise behind her. What was that?
Great: Just great.

This turned into a mess. Arcadia took no damage, and she was never in danger, but it was annoying.
Demons and spider and snakes (sorry guys: you don't deserve an "Oh, my!")

Back to the beholders. Same game plan as before: buffs->Skull Trap x 3 Sequencer->Ages


Only one left now.

Why is this guy out of place? He bounced Telekinesis off of Spell Turning, and consequently wing buffetted himself.

Can anyone guess what Arcadia is doing here? (this picture is not out of sequence)

Am I the only one who has bad memories of this spawn, from back in the days when I first started playing?

Congo line.

Once again, Mr. Efreeti got the kill against the Unseeing Eye: Rod-> Efreeti Fireball.

Last beholder crew



I'm sorry: Are you lost?

Note to self: Now that Arcadia has Black Blades of Disaster, be careful with them, ok? Don't just run around vaporizing loot.

Arcadia is definitely looking forward to BBoD->Improved Alacrity->Greater Whirlwind + Critical Strikes with 25 strength. Even with a strength of 18, the BBoD yields solid criticals.

I'm not sure what's next. Kangaxx? Twisted Rune? Bodhi? Not sure?
Best,
A.