Professor R. B. Magick's Mobile Emporium of Arcane Wondries

Professor R. B. Magick stands nearly 6 feet tall with his high heeled black boots, and seems taller with the brightly colored silken garbs that hang loose from him.  He makes a point to twirl often to allow the bright colors to dance on the air about him, as if he himself were magical.  His voice dances similarly as he speak, using all of his bardic knowledge to inflect and sing the words for maximum effect.  He is mostly a salesman and he sells amazing magic items and surprisingly reasonable prices (half book prices) before moving on to the next town with his brightly colored mechanic contraption of a sales wagon.

Every now and then, though, he takes a detour through an unknown alley in a city he'd rather not mention.  This alley is where the rejected magical items from the local mage school get dumped for disposal.  Unfortunately the fence is not so high that it can't be climbed and the incinerator furnace is not run so often by the groundskeeper.  The Professor finds his magical items.

It takes a very keen eye (DC 15 Perception or Arcane Knowledge) or an unlucky use to determine the problems with these items.  Some of them are weaker than they should be.  Some of them have nasty side effects, or perhaps the primary effect has been warped somehow.  In other cases, a misspelled rune makes the object do something altogether different.  And once in a while the item behaves as normal.

The Professor always mixes in a few normal items that he keeps track of for demonstration so no one will know until his wagon is long gone.

Here are some example magic items to be sold (suitable to be rolled on a d20), with the items they appear to be given in parentheses.  The items function normally with the exceptions given.

1. Wand of Bless You (Wand of Bless) -- functions normally, except the target spends their bonus action each round sneezing for the duration
2. Wand of Feather Wall (Wand of Feather Fall) -- instead of having the effect of feather fall, the wand places a wall of feathers at the impact point of the falling person, reducing falling damage by 1d10.
3. Wand of Maid Armor (Wand of Mage Armor) -- The target is dressed in a French maid's outfit, and the base armor class of the target is set to 11 + their DEX modifier.
4. Wand of (Almost) Silence -- Works as the spell silence, except that sounds at a shouting level can propagate and be heard.
5. Scroll of (Almost) Sleep -- Instead of sleeping the target become very drowsy and falls prone, but is otherwise unaffected.
6. Scroll of (Almost) Witch Bolt -- Instead of an instantaneous blast of blue lightning, a witch flies at the target and hits doing 1d8 damage.  This can be continued each round per the normal spell.
7. Scroll of (Almost) Rope Trick -- The spell acts normally except that it only lasts 30 seconds.
8. Wand of Magic Thistle (Wand of Magic Missle) -- Instead of missiles, a crop of thistle crops up around the target, causing the 5 foot square to become difficult terrain and causing 1d4 damage.
9. Scroll of Fire Faerie (Faerie Fire)  -- Instead of outlining the target in flame, a faerie appears and shoots flame at the target doing 1d10 damage (Reflex Save for half damage) and setting any flammable items it is carrying on fire.
10. Potion of (Purple) Healing -- The target is healed normally, but also turns purple for 1d4 hours
11. Potion of (Nearly) Invisible -- The target turns invisible, but the spell does not affect the target's clothing or carried items.
12. Potion of (Too) Invisible -- The spell functions normally but one random item the target carries is permanently turned invisible.
13. Scroll of Comprehend Most Languages -- The spell functions normally except that the target has their ability to normal common language randomly switched to another language for 24 hours.
14. Scroll of (Involuntary) Levitate -- When cast, the spell automatically targets the caster and maintains the caster at a fixed altitude of 20 feet.  It lasts for 1d4 hours without concentration.  The caster cannot end the spell and gets no save.
15. Potion of Speak to (and Kill) Plants -- The spell functions normally except that all of the plants die when the spell ends.
16. Scroll of (Not) Truth -- The spell functions normally, except the affected creature can only speak lies, instead of truth.
17. Potion of (Weak) Spider Climb -- The spell functions normally except that automatically ends if the target reaches says the word "spider"
18. Scroll of Putrify Food and Drink (Scroll of Purify Food and Drink) -- The spells works normally except that the food and water become completely putrid.
19. Goodlarry (Goodberry) -- The spell produces a human named Larry of good alignment instead of berries.  Larry is confused.
20. (Altered) Colorspray -- The spell functions normally except that targets are instead painted with rainbow colors.  Attacks against them have advantage as with faerie fire until the paint is removed using an action.