Remember first that it's written for RQ2. Invisibility is a battlemagic spell, and one point of TK works up to SIZ 20.
Even moderately intelligent PCs will start with recon. A bound spirit in any kind of inconspicuous flying animal will tell you right where the table is, and that there's only four guards on the roof.
Clever and skilled Orlanthi initiates (Orlanth for TK or, if they're Rune-rich, Guided Teleport) should be able to take the roof without that much difficulty; maybe even without raising an alarm, if they add Silence and pre-cast a few Befuddles from cover. Also, don't forget the other RQ2 POW v POW spell: high-POW attackers should be able to Harmonize one or two guards and walk them right off the roof. Thud.
If you don't have Orlanth rune magic, well, it depends on whether you houserule that Darksense can see through Lightwalls. I don't think it should be able to, personally. Properly positioned Lightwalls should mean the trolls can't drop rocks at better than 10%.
Even if it comes to a toe-to-toe fair fight, I would think there's a lot of experienced PCs who can, if they have to, put up a few points of Shield and handle a troll maul that's only got Bludgeon 2. 2d8 + 1d6 + 2 is only 14-15 points on average; plate mail plus Pro 4 plus Shield 2 makes that bounce. RQ2's Vigor means even a substantially above-average hit doesn't break a limb if your CON is decent. And this all assumes the troll can get past your parry mastery.
Strong PCs with BS 4'ed bastard swords, on the other hand, are doing 1d10 + 1 + 4 + 1d6 (average 14), with higher skills, against 7-point armor. Average hits break limbs and the trolls' parry is only 50%. The uz should go down fast.
Of course, there's a /lot/ of trolls that would begin arriving soon, and the commandos are a bit tough even for skilled initiates. But if all they want is the Table, well, from the roof it's right down there in the courtyard, and it's supposed to be "portable", so it's hard to believe it's more than 100 ENC - -- which means one more TK or, if Orlanth has been nice to you, a sylph; not a bad runespell investment for 350 wheels of reward.
Once you have the table it's just a footrace, and Mobility, especially on a waiting mount, should win that. Jumping is annoying, but you can always change direction once they're committed -- and once the no-stored-POW trolls have cast Jump a few times on top of their Bludgeon and Countermagic and are at about four POW, PCs with stored magic points (and thus presumably still at full casting POW) should be able to demoralize and harmonize more or less at will, even with the extra POW to blow past the CM 1's.
Now, RQ3 poses a few more problems, mostly that flying is much more expensive, and invisibility and harmonize aren't easy or common. But then again RQ3 has acolytes, and thus Rune magic flies much more freely (and with more Rune magic you have far more options, and with enchantments you probably have more stored POW). And RQ3 has Dodge, which doesn't require Repair spells.
All told, I wouldn't have hesitated to run my current PCs through this, even quite a while ago, so long as they had attack and parry masteries and some Rune magic. They probably wouldn't have been captured (though they might have run away and regrouped once). But I wouldn't run this adventure without giving the trolls a believable amount of Rune magic, which means I'd probably fiddle with it a bunch overall.
Consider, too, that RQ is set up to have viable nonhuman PCs. Troll PCs would find this a very different (and much more interesting) adventure. (And even using the same tactics, PC uz will presumably have Jump, which makes the roof trivial.)
No, it's not for beginners. If you don't have full-up battlemagic (Pro 4 and BS 4), some skill masteries, and some appropriate Rune magic you're not up to it. But IMO it needs only minor editing changes (and only in the emphasis: don't assume there's only one way in) to be a challenging but perfectly doable adventure for near-Rune PCs. I found the Krarsht tunnels scarier.
End of The Glorantha Digest V7 #150
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