At the most recent session, a character was out looking for items. In our saga crafty magi and enchanters might display their wares as examples for commissions. I mentioned a booth with very few items, each displayed carefully, and the characters asked after a ring, of the covenfolk attendant.
"Ah, this fine ring turns the user invisible."
"Does it turn invisible?" asks the joker in the group (who has a bad case of bathos).
Which promptly descended into a series of jokes about botched magic items. (I would often find this annoying, but it broke up a slow part of the session.)
Afterward, I was thinking about this, and noted that most magic items don't involve a roll, but experiments do.
It brings up the question, what interesting/dangerous/useless botched items are out there? Have any shown in your games?
We had a wand of Abysmal Ducks - you aim it at a target, a duck flies at the target and explodes for great damage - not quite as impressive as a wand of Abysmal Flame, but it had a certain comic charm.
One of our beta storyguides stutters severely when under pressure. All of us, and him most of all, make fun of this peculiarity of his. He introduced in the game a wand shooting Balls of Abysmal Fire with impressive Penetration, enchanted by a Verditius NPC with a stutter.
The trigger was supposed to be "Ball of Abysmal Fire!", but due to an experimentation quirk it ended up being "B-b-baa-ball of A-A-AAA-by ssss Abysmal F-F-F-F-Fire!". Com stress roll of 3+ to get it off, and a 3-point penalty to Initiative; double that if the player does not actually recite it correctly.
The funniest time we had was after a PC, with no stuttering problem but the Minor Personality Flaw: Stingy, had purchased the wand on the cheap. Fighting side-by-side with his cold-hearted Tremere love interest in a difficult battle, he tried to activate the wand. ""B-b-baa-ball of A-A-AAA-by ssss Abysmal F-F-F-Fire!" - clearly incorrect, so the wand just sputtered. "How can you be so stupid as to use a wand with a verbal trigger, when you have such an obvious stuttering problem?" she spat angrily. We laughed for ten minutes straight!
An enchanted flying ship that, christened with Faerie wine, developed a weakness for fine wine. She will fly all right, but only if she gets to guzzle wine like a tank guzzles fuel - and beware the fool who thinks of transporting a shipment of wine in her hold.
A feather cloak to turn the user into a songbird that infallibly attracts any nearby, hungry birds of prey.
A brooch that allows the user to speak with animals, but makes him sound incredibly boorish and insulting.
This is actually a good, subtle minor side-effect: a Wings of the Soaring Wind device that also collects, over a few minutes, water vapour just below its user, so from the ground he looks like a cloud.
Another good side effect: Boots of the Seven Leagues Stride that, if possible, subtly adjust the user's arrival so that it was no witnesses.
A device casting Maintain the Demanding Spell at D:Ring (really, really common in our sagas) that somehow does not work by creating a Ring, but a Square. Not bad, just ... strange. All magical investigation shows it's perfectly Hermetic, and any attempt to replicate the design using the Lab text creates normal, "Ring" effects.
No, as I recall it was a ritual spell to conjure trees. But the spell was Warped because it was designed in a faerie regio, where my magus had to stay for one season a year until he found a replacement to take his place. The Herbam bonuses were pretty good so long as I wasn't doing anything that might explode in my face (experimenting).
Quite a few over the years, some I recall off the top of my head are:
(not all negative and one might be faerie)
Eggs which when broken (e.g. thrown at someone) casts "Stench of the twenty corpses", but the effect also causes a loud bang.
An invisibility cloak which only makes you invisible from behind.
A wand which temporarily transforms an amount of air to stone at a range, but which must be aimed by describing the locations (aim with Com+Latin instead of the usual Per+Finesse).
A wand which can enlarge an animal (+2 size), but which will also reduce the size of the user (-1 size).
A ring of "invisibility" which when donned creates a small cloud of very dense and opaque mist which follows the wearer around.
A masterfully crafted sword which when used in the right hand flames and causes +5 fire damage, in the left hand if freezes and causes +5 cold damage. After three rounds the sword becomes too hot or cold to use unless you switch hands.
A metal rod which can transform into any weapon you know how to use, but which never hits its intended target no matter how you try.