Head of Vecna
Many years ago (back when we all were still playing D & D), I ran a game where I pitted two groups against each other.
Several members of Group One came up with the idea of luring Group Two into a trap. You remember the Hand of Vecna and the Eye of Vecna that were artifacts in the old D&D world where if you cut off your hand (or your eye) and replaced it with the Hand of Vecna (or the Eye) you'd get new awesome powers? Well, Group One thought up The Head of Vecna.
Group One spread rumors all over the countryside (even paying Bards to spread the word about this artifact rumored to exist nearby). They even went so far as to get a real head and place it under some weak traps to help with the illusion. Unfortunately, they forgot to let ALL the members of their group in on the secret plan (I suspect it was because they didn't want the Druid to get caught and tell the enemy about this trap of theirs, or maybe because they didn't want him messing with things).
The Druid in group One heard about this new artifact and went off in search of it himself (I believe to help prove himself to the party members...) Well, after much trial and tribulation, he found it; deactivated (or set off) all the traps; and took his "prize" off into the woods for examination. He discovered that it did not radiate magic (a well known trait of artifacts) and smiled gleefully.
I wasn't really worried since he was alone and I knew that there was no way he could CUT HIS OWN HEAD OFF. Alas I was mistaken as the Druid promptly summoned some carnivorous apes and instructed them to use his own scimitar and cut his head off (and of course quickly replacing it with the Head of Vecna...)
Some time later, Group one decided to find the Druid and to check on the trap. They found the headless body (and the two heads) and realized that they had erred in their plan (besides laughing at the character who had played the Druid)...The Head of Vecna still had BOTH eyes! They corrected this mistake and reset their traps and the Head for its real intended victims...
Group Two, by this time, had heard of the powerful artifact and decided that it bore investigating since, if true, they could use it to destroy Group One. After much trial and tribulation, they found the resting place of The Head of Vecna! The were particularly impressed with the cunning traps surrounding the site (one almost missed his save against the weakest poison known to man). They recovered the Head and made off to a safe area.
Group Two actually CAME TO BLOWS (several rounds of fighting) against each other arguing over WHO WOULD GET THEIR HEAD CUT OFF! Several greedy players had to be hurt and restrained before it was decided who would be the recipient of the great powers bestowed by the Head... The magician was selected and one of them promptly cut his head off. As the player was lifting The Head of Vecna to emplace it on its new body, another argument broke out and they spent several minutes shouting and yelling. Then, finally, they put the Head onto the character.
Well, of course, the Head simply fell off the lifeless body. All members of Group Two began yelling and screaming at each other (and at me) and then, on their own, decided that they had let too much time pass between cutting off the head of a hopeful recipient and put the Head of Vecna onto the body.
SO THEY DID IT AGAIN!... [killing another PC]
In closing, it should be said that I never even cracked a smile as all this was going on. After the second PC was slaughtered, I had to give in (my side was hurting)...
And Group Two blamed ME for all of that...
The story was memed all over the place; Knights of the Dinner Table included an homage in its "Head of Vectra".
TSR found this absolutely hilarious, and so the Head of Vecna actually appeared in their final 2e module, Die, Vecna, Die! alongside the other legitimate Fragments of Vecna. It was a classic AD&D style trap, and would be absolutely worthless to anyone who tried to add it to their own body; unlike the Heart, it would not bring a new host back from the dead.
In Planescape: Torment Morte has two conversations where he says that he is the head of Vecna, or possibly one of the dupes tricked by it. While these are presented as a joke, Morte's origin (before he was on the Pillar of Skulls, at least) is never discussed otherwise.
Wizards, also found epic lulz in this and so, much later, someone decided it would make a great April Fools joke campaign, and worked it out as an official quest for 3.5. In the official quest, the Head is real, but horribly inconvenient in the fact that it has to be placed on a LIVING headless body, requiring a high-level spell (raise dead won't cut it) to bring them back. On top of that, the powers of the head are useless and cause permanent stat damage. All in all, a great way to screw with your party.
The powers of the head are determined by a d6 check when the head is attached:
- The head is powerless and the PC dies
- The head spins during combat, Poltergeist style, giving all around vision (no flat-footed or surprise attacks). After 2 turns, you have to pass a Concentration Check (DC15) to do ANYTHING. After 2 more rounds, the user falls prone, dizzy, and incapacitated. It takes 10 minutes to recover, and you lose 2 DEX until the head is removed.
- The head will spout useless opinions on irrelevant topics, and a DC20 Willpower check must be passed in order to do anything, otherwise the head takes control. -2 Charisma until removed.
- The user gets "rose tinted glasses" that cause them to see whatever they want. This means opening a Mimic's mouth will make the user see piles of treasure. -2 Wisdom until removed.
- The head will randomly swap with the heads of other creatures in the immediate area once attached successfully. The victims retain their original personality, NOT the one of the head they end up with. Anyone who's suffered this can swap for their original head, but not the Head of Vecna. ANYONE who has been the target of a swap loses 2 INT that can only be restored by a Miracle or Wish.
- The user gets two spell-like abilities chosen at random from the Wizard or Sorcerer classes (d6 for level, then pick one of the level from PHB). It's a once-per-day ability, it changes every day, and each time it happens the user loses two CON. Again, removing the head will fix it.
Case in point: check your source books.
Third edition's Fiendish Codex II included a subtle nod to it, in a magical location called the Pillar of Geryon, which severed a hand placed inside it and replaced it with one that did extra damage. The lore checks associated with the location are written to trick players into offer their heads to it instead, suggesting that it might give more power on a check of 20, and revealing that it will just kill you on a 25.