Firework Wand

 Here's a useful low-level Wand for your D&D game. It's an upgraded version of the Wand of Pyrotechnics from Xanathar's Guide to Everything, rendered more useful (and less harmless) but still weak enough that you could give it to 2nd level characters without it wrecking game balance. 

Wand of Fireworks:  (Wondrous Item, Wand, Rarity: Uncommon).   Description: This redwood wand has a blackened tip that faintly glows with a smouldering inner red light like an old coal not quite extinguished. Despite this appearance, it's not particularly warm to the touch.
Properties: This wand has 7 charges. While holding it, you can use an action to pick a target creature, item, or space that you can see within 120 feet, expend a charge, and decide whether you want the effect to be harmless or dangerous.
The harmless effect is a burst of multicolored light and sparks. The burst of light is accompanied by a crackling noise that can be heard up to 300 feet away. The light is as bright as a torch flame but lasts only a second. The controller may choose the color of the flames.
The dangerous effect is as above, but the flickering firework is briefly hot enough to actually burn things or start small fires. The target must succeed on a DC 12 Dexterity saving throw, or else suffer 1d10 fire damage. If the target is a flammable object, it ignites if it isn’t being worn or carried.
The wand regains 1d6 + 1 expended charges daily at dawn. If you expend the wand’s last charge, roll a d20. On a 1, the wand erupts in a harmless pyrotechnic display before burning down to ash, destroying itself. 

It's basically the Wand of Pyrotechnics, plus an optional damaging effect that's a modified version of the Fire Bolt cantrip. 

Clever characters will quickly figure out its not a great attack, and often better used for distractions or signalling. The color-change aspect was added specifically to empower that utility, so that even if that's all you're using it for, it's a minor improvement on the Wand of Pyrotechnics. Evil characters will quickly figure out that it's even better for arson.

Why'd I make such a thing? Well, I'm gearing up for some D&D on Roll20 over the New Year. At the end of the previous session, the PCs had surprised me by searching a place that totally made sense for a recently deceased NPC wizard to have hidden something. In fact, it was unintentionally implied by something I'd narrated, and they'd picked up on my unintended implication. I'd been focused on the main plot, and had nothing prepared for this hidden stash, but wanted to reward their clever thinking. Since it was near the end of the session, I told them they found a wand hidden there, and left the discovery of what type of wand for next time.

Well, "next time" is almost here, and I've made myself a minor problem. My characters are just third level, so there's not really a good wand for them.

A Wand of Magic Missiles is probably a too large step up in offensive power. Even at just using 1 charge per turn, it's 6-21 guaranteed damage per turn at a time where the PCs are still rolling a single damage die and no one has Extra Attack yet. Dropping 4 or 5 charges would vaporize the campaign's current big bad in a single turn. So that's out.

Xanathar's Guide to Everything has some common Wands, but I hadn't read through them yet at the time. They're cute, kinda fun, but have sort of the opposite problem of the Magic Missiles: they aren't useful in a fight at all. If the dour old wizard hid away a wand for safe-keeping, it's got to be a little better than making people scowl, or grow a single flower. My players were excited at finding a wand because there have been relatively few magic items in the game, and now they've had some time to imagine what the wand might be and do, so it's possibly built up a bit in their minds.

Unfortunately, all the Uncommon Wands are either too powerful for the current moment in my game (Magic Missiles, Web), or so limited as to be nearly useless (Wand of Secrets in a group that already has two Rogues with pretty decent Perception/Investigation skills).

So I need a wand that's a little more useful than any of the common Wands in XGE, but not such a step up that it causes the group's fighter or one of the rogues to give up their normal attack in favor of the wand for the first two rounds of every combat. Something that's cool and useful, but requires some cleverness to get the most out of.

I went with an custom upgraded version of the Wand of Pyrotechnics because it fit nature of the deceased NPC wizard: he was a bit of a show-off in his youth, but was old and frail and not so great at magic anymore. This wand was his crutch. D&D doesn't really have provisions for growing old, so there's no official reason why he couldn't just use a cantrip that would probably do more damage since he was at least a 5th level wizard in his youth, but it makes narrative sense for him to have lost most of his magical edge in his final years. The "old coal not quite extinguished" was a pretty apt metaphor for the character before he was murdered.

Also, currently the PCs are at odds with the local Duke, and I like the idea of them being tempted by the newfound ability to burn down the Duke's manor. I think that will lead to some fun role-play moments as they debate the ethics of such skullduggery.