Soloing BG2:Soa and BG2:Tob

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Has anybody soloed BG2:Tob?

I have tried twice to solo BG2:Tob however I can never defeat the six shadow slayers that melissan summons in the final battle.

I soloed an elven wild mage to melissan final fight and also a half-elf kensai to the final fight only to be annihilated by the six shadow slayers.

I am now attempting to solo an elven fighter/mage through BG:EE to BG2:Soa and BG2:Tob. Perhaps the fighter mage has the DPS to defeat the six shadow slayers while I hope Melissan doesn't summon any elder orbs.

Gallowglass

You don't actually need to defeat the Shadow Slayers, you just need to beat Melissan.

The main danger from the Shadow Slayers is their level-drain, so you need to equip a weapon (or other item as appropriate for character class, such as the Amulet of Power) which gives negative plane protection. Then one approach you can try is just to ignore the Shadow Slayers, and concentrate on attacking Melissan. With a bit of luck, she'll go down before you do, and the Shadow Slayers will then immediately unsummon. I haven't tested this in the scenarios you mention, but certainly it works in other cases and might work in your cases.

BTW, if I recall correctly, that's not the final fight with Melissan, there's one more after that, but easier.

Arunsun

Soloed both SoA and ToB with a Dark Moon Monk (already trained to max level before) in insane, except for Amelyssan fight, I had to lower difficulty due to unwillingness to load a save before fight and buy some cold resist scroll.
The best solution is to focus Melyssan and ignore Slayer Shadow if you can. Not that hard with Wild Mage + spell immunity: abjuration(for dispel) + PfMW considering your number of spell cast+ wish: rest

By the way, Dark Moon Monk, and I believe monk overall, are very strong at soloing the game due to very high level scaling and low need for specific, hard to get equipment. Basically you want gauntlet of crushing, ring of Gaxx, some ToB Rasaad Quest item (just allowed him in my team to get the quest started) and you can easily take any fight.
I am not an expert, but the gear I advice to get as soon as possible for monk is:
Gauntlet of crushing (Help Ixilthetocal in city of cavern)
Ring of Gaxx (you'll need to wait your fists to be +4 weapon, then Kangaxx quest)
Ring of protection +3
Headband of the devout (Rasaad ToB quest)+one of the AC Ioun stone
Dark moon Cloak (Rasaad ToB quest)
Night Walkers (Rasaad ToB quest. Boots of speed works as well, I do advice to keep Cold Resist boots for Melyssan)
Seldarine amulet
Strength Belt

In the end a Dark Moon Monk with appropriate potions and buffs should have, -24 AC which basically gets you hard to hit with mirror Image, 100% magic resistance, and still huge damage (25strength with Righteous Magic from the Headband, that is 43 damage per attack if I m not mistaken)
You might have to try several times ravager and Amelyssan fights though