But the wearer of the green boots of Elfland may not fall or be thrown to land other than on his feet.
Roger Zelazny - Dilvish the Damned
D&D's Boots of Elvenkind are supposed to be drawn from Roger Zelazny's Dilvish the Damned stories. If so, Gygax missed pillaging a few other magic items from the same stories:
Mildin shuddered and fetched her shimmering were-cloak--for she was Mistress of the Coven--and throwing it about her shoulders and clasping it at her neck with the smoky Stone of the Moon, she became as a silver-gray bird and passed out through the window and high about the Denesh.
Obviously a were-cloak lets you change form. I'm not exactly sure what the Stone of the Moon does. Something fey, I bet.
The guards had cornered the slayer. He fought them, apparently empty-handed, but parrying and thrusting as though he gripped a blade. Wherever his hand moved, there were wounds. He wielded the only weapon that might have slain the King of the World, who permitted none to go armed in his presence save his own guard. He bore the Invisible Blade.
It's hard to know how to stat the Invisible Blade. Does it get a bonus to hit because it's so hard to parry? If so, how is it different from other magical swords which also get bonuses to hit? Does it allow a thief-like backstab on the first strike?
To be fair to Gygax, he didn't entirely miss the Invisible Blade. He statted it up, but buried it in near obscurity: in the character sheet of Gellor in the afterward to "Saga of Old City". In the enworld Q&A he says:
As for the invisible sword that Gellor had, it was not in play in my campaign--not to say I hadn't maybe placed one somewhere 😉 Aside from its plusses to hit and damage, the weapon allowed its wielder to see any otherwise invisible foe and to attack first in any normal exchange. Of course there was a command word for it to come to hand--pretty hard to locate your invisible sword without that... If it was within range of the possessor's voice it woulc fly instantly to that own's hand.
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