Please help me make cool weapons

Ayo. I need some help making cool weapons for my campaigns, my friend black bear suggested the axe gun, so I want some more inspiration for stuff like that. Please help me.

This isn't "arts and craft"  more "general discussion". But I'll give a few suggestions.

Chain sword. A finesse sword with reach. Slashing damage within 5ft 1d6, piercing damage at 10ft 1d4.

Bolo. Short ranged weapon 1 point damage with the ability to either grapple or knock prone medium or smaller creature.

Spiked guantlets. Gives unarmed strikes 2 + strength modifier.

Arts and craft is all about what you've physically made. A little paper, clay, glue, 3d modeling even.

K thx

I like how you think! I have weapon ideas bananza! Though, do you want magical weapons? Or non magical?

Yeah, I don't know if you want magical or non-magical, but here are some cool magic weapons (well, I think they're cool) I found on D&D Wiki: 

Illogical Weapon

Weapon (any), rare

Although it looks and feels like a regular weapon, the Illogical Weapon acts strangely when used. While a regular sword inflicts slashing damage, an Illogical Sword might inflict piercing. And while a regular bow inflicts piercing damage, an Illogical Bow might inflict bludgeoning.

You gain a +1 bonus to attack rolls and damage rolls made with this magic weapon. Every dawn, and every time you roll a critical hit with this weapon, roll a d6 on the Illogical Damage table. The Illogical Weapon now inflicts that type of damage until the next dawn or critical hit, when you roll another d6. On a hit, you may also cause an effect related to the damage type described below in the Illogical Damage table as a bonus action. You regain use of this effect after you finish a short or long rest.

Sharpshifter

Weapon (varies), rare (requires attunement)

This black piece of amorphous metal looks like nothing more than a large chunk of obsidian when no one is attuned to it. When it has an attuned wielder, that wielder can morph and change the weapon's shape as a bonus action. It can shift into any known mundane weapon. It can also shift into any other shape that the DM deems doable with the amount of metal available. Sharpshifter can also take the form of armor for a section of the body (about one limb, half of a torso, or helmet). This armor grants the wearer +1 AC. If attunement is ever broken, Sharpshifter returns shape to it's rock form, sliding off the current wearer or wielder.

Yo-Yo of Dooooooom

Weapon (yo-yo), rare (requires attunement)

A child's toy left that has been enchanted by a old and senile magician who wanted to turn his towns next generation into warriors at an early age. This yo-yo was the magicians last work, discovered after the parents of the children killed him. The yo-you can emit an ominous glow, casting dim light within 20 feet. This effect may be turned off or on as a bonus action. This weapon deal 2d6 extra necrotic damage.

Heres the thing. I want ALL the weapons. (And vehicles). Magical and no magical. D&D B is the limit!

Quote from Yondor_The_Fantastic >>

Yeah, I don't know if you want magical or non-magical, but here are some cool magic weapons (well, I think they're cool) I found on D&D Wiki: 

Illogical Weapon

Weapon (any), rare

Although it looks and feels like a regular weapon, the Illogical Weapon acts strangely when used. While a regular sword inflicts slashing damage, an Illogical Sword might inflict piercing. And while a regular bow inflicts piercing damage, an Illogical Bow might inflict bludgeoning.

You gain a +1 bonus to attack rolls and damage rolls made with this magic weapon. Every dawn, and every time you roll a critical hit with this weapon, roll a d6 on the Illogical Damage table. The Illogical Weapon now inflicts that type of damage until the next dawn or critical hit, when you roll another d6. On a hit, you may also cause an effect related to the damage type described below in the Illogical Damage table as a bonus action. You regain use of this effect after you finish a short or long rest.

 

Sharpshifter

Weapon (varies), rare (requires attunement)

This black piece of amorphous metal looks like nothing more than a large chunk of obsidian when no one is attuned to it. When it has an attuned wielder, that wielder can morph and change the weapon's shape as a bonus action. It can shift into any known mundane weapon. It can also shift into any other shape that the DM deems doable with the amount of metal available. Sharpshifter can also take the form of armor for a section of the body (about one limb, half of a torso, or helmet). This armor grants the wearer +1 AC. If attunement is ever broken, Sharpshifter returns shape to it's rock form, sliding off the current wearer or wielder.

 

Yo-Yo of Dooooooom

Weapon (yo-yo), rare (requires attunement)

A child's toy left that has been enchanted by a old and senile magician who wanted to turn his towns next generation into warriors at an early age. This yo-yo was the magicians last work, discovered after the parents of the children killed him. The yo-you can emit an ominous glow, casting dim light within 20 feet. This effect may be turned off or on as a bonus action. This weapon deal 2d6 extra necrotic damage.

 I love the yo-yo

Check the homebrew in my sig, its full of weapons

Bolo. Short ranged weapon 1 point damage with the ability to either grapple or knock prone medium or smaller creature.

kodi nox 

Small knife that does (1d4 percieng and has a bullet you can shoot out the handle (1d8 percing)

Quote from Chaco_King >>

Small knife that does (1d4 percieng and has a bullet you can shoot out the handle (1d8 percing)

I will give this a small nod for realism - there actuall were a number of early weapon-firearm combos like knife-guns and even axe-guns. They were typically show-off or novelty items, as the combination usually made each part worse (poorly weighted or difficult to weild as a knife or axe, difficult to aim and hold as a gun. I am a little skeptical of 1d8 from the gun, and range would be short, but these were a real thing.

This is definitely not in the right section of the forums.

But, in terms of gameplay mechanics (if you care about things like game balance).  You have to think about a lot when you create content for a game.  For example - 

Axe Gun :
I don't know what stats you're thinking about for this, but it sounds like a melee weapon which is also a ranged weapon.  So, are there any downsides to it?  Normally, switching weapons is a limiting factor in the game.  If your melee weapon is also your ranged weapon you're potentially skipping some gameplay mechanics like drawing and stowing weapons.

If you want to ensure you've got something balanced and if you're not familiar with how to build things in the game ... the best thing to do is reflavor things.  Change the description and leave everything else the same.

Want a melee weapon that is also a ranged weapon?  Pick a weapon that can be thrown which is already balanced to have those capabilities.  A trident or a handaxe would be a great place to start.  The numbers of the thing stay the same, you just change the description. 

if you start to make adjustments to things beyond this you very quickly run the risk of breaking the balance of your game.  And, 90% of player made content is extremely poorly balanced and causes issues.

Axe-d'rbuss - 
It's an axe and a blunderbuss.  Devastating in melee and also close ranged combat.
1D8 damage
versatile (1D10 damage two handed)
20/60 range

Think of an idea you like.  Look for something that already exists that may be close to what you need (mechanically), then change the description. If you need inspiration for ideas, look at fantasy content.  You can use the throwing star from Krull.  You can use a whip-sword from a dozen different shows and movies and games.

Or, you reduce the impact of both. Your axe-gun does 1d4 as an axe and 1d6 as a gun, or has disadvantage to hit as a gun, and cannot be used as a ranged weapon and a melee weapon in the same round. Using it as a melee weapon upsets the priming, and requires an additional round to re-load after a melee attack, etc.

IRL combo weapons were almost always worse than the seperate weapons.

Quote from RangerFalin >>

Or, you reduce the impact of both. Your axe-gun does 1d4 as an axe and 1d6 as a gun, or has disadvantage to hit as a gun, and cannot be used as a ranged weapon and a melee weapon in the same round. Using it as a melee weapon upsets the priming, and requires an additional round to re-load after a melee attack, etc.

IRL combo weapons were almost always worse than the seperate weapons.

 
But, this is worse than using pretty much any melee and ranged weapon combination and using the weapon swapping rules to move between them.

A handaxe does 1D6 damage as an axe, and also 1D6 damage when thrown with a range of 20/60.  No wasting a round if you move between attacks. Just carry a couple super inexpensive handaxes.

To say nothing of using the stow draw rules to .... draw a greatsword as a part of your attack action and attack with it. And, stow it as a free utilize action and for the next round draw your longbow or heavy crossbow as a part of your attack action.

There's another issue with the weapon concept, too.  An axe is a strength based weapon and the gun would be a dexterity based weapon.  Fundamentally this would be really difficult to use and to build for.

It's actually really hard to make a good thing.  Homebrew is rarely good.

The thing you've created is balanced poorly.

Quote from 

But, this is worse than using pretty much any melee and ranged weapon combination and using the weapon swapping rules to move between them.

...

There's another issue with the weapon concept, too.  An axe is a strength based weapon and the gun would be a dexterity based weapon.  Fundamentally this would be really difficult to use and to build for.

It's actually really hard to make a good thing.  Homebrew is rarely good.

The thing you've created is balanced poorly.

 
To be clear, I wasn't the one proposing the original knife-gun. I was just suggesting these did exist IRL, but didn't work well because they were worse than either weapon on it's own. And in-game it has issues as you suggest, due to strength-melee vs dex-ranged. 

Most attempts to build combo weapons seem to be about making OP range/melee combos that do both better. I'm suggesting nerfing them to prevent that, so it does make more sense to just throw a few spare handaxes. Then the gagety rogue might still carry a dagger-gun concealed in their sleeve while sneaking into the Duke's royal ball, because it fits their character to have a single concealed weapon, despite the drawbacks, and doesn't become "I can hit one enemy with the axe at the same time shooting another across the room, and they both auto-crit and do smite and hex and hundreds of points of damage per round."

Quote from RangerFalin >>

Quote from 

But, this is worse than using pretty much any melee and ranged weapon combination and using the weapon swapping rules to move between them.

...

There's another issue with the weapon concept, too.  An axe is a strength based weapon and the gun would be a dexterity based weapon.  Fundamentally this would be really difficult to use and to build for.

It's actually really hard to make a good thing.  Homebrew is rarely good.

The thing you've created is balanced poorly.

 
To be clear, I wasn't the one proposing the original knife-gun. I was just suggesting these did exist IRL, but didn't work well because they were worse than either weapon on it's own. And in-game it has issues as you suggest, due to strength-melee vs dex-ranged. 

Most attempts to build combo weapons seem to be about making OP range/melee combos that do both better. I'm suggesting nerfing them to prevent that, so it does make more sense to just throw a few spare handaxes. Then the gagety rogue might still carry a dagger-gun concealed in their sleeve while sneaking into the Duke's royal ball, because it fits their character to have a single concealed weapon, despite the drawbacks, and doesn't become "I can hit one enemy with the axe at the same time shooting another across the room, and they both auto-crit and do smite and hex and hundreds of points of damage per round."

Sure thing!  Think of an item used in media anywhere.  Copy it.  That's generally the initial birthplace of creativity.   It's a solid place to start.  The trick is making adjustments so the comparison is less direct, or picking something obscure.  What will make it memorable will be the description.

For game balance (glad to hear you're thinking about it!) try to use a real thing and just change the description.  As an aside this is the best way to create enemies as well.  So, if you want a super badass goblin captain, don't create it from scratch as for most this will be an unbalanced mess ... instead ... use a small dragon and change the description of the creature and abilities. You get the same effect in game, but you know it's reasonably balanced because it's from the monster manual. 

Try combining a wondrous item (even a simple uncommon one) with a weapon.  The uncommon item is balanced.  A normal weapon is balanced. There's a minor balance issue in that these wondrous items are designed to take up a slot and this bypasses that.  However, that's rarely an issue at lower levels and the most critical limiting factor is attunement (never drop attunement).

Watch some fantasy and sci-fi.  There were interesting weapons in the D&D animated series (like the energy bow and the growing staff).  The throwing star from Krull.  Any weapons from Mortal Kombat.  The whip/sword I mentioned.  

Rare Magic Sword - Sword of Tiger's Leap
+1 magic longsword that requires attunement.  Your speed cannot be lowered below 30.  Once on each of your turns you can jump up to 30feet by spending only 10 feet of movement.
(this is just the boots of striding and springing attached to a sword and two uncommon items combined to make it a rare)

Uncommon longbow - Bow of the Hunt
Requires attunement.  Anyone using this longbow has proficiency with it.  Also, the user gains +2 to damage rolls with this weapon.
(this is just the bracers of archery wondrous item given to a longbow)

Uncommon orb - Sphere of Eruption
While using this spellcasting focus (use any focus for any class any of your players have) the user can cast scorching ray with +5 to hit.  This feature can be used once per day.
(this is just the circlet of blasting added to a spell focus ... you could also put this on a weapon ... like once per day a hand crossbow could launch the scorching ray blasts)

Rare Maul - Woeful Crusher 
+1 maul that requires attunement.  Strength of the user becomes 19 while wielding it.  Has no effect on anyone who has a strength of 19 or higher without the maul.
(this is just the gauntlets of Ogre Power attached to a +1 weapon)

Rare Axe - Shielding Axe
+1 battleaxe that requires attunement.  If you're hit by a ranged or thrown weapon while wielding this axe you can take a reactio nto reduce the damage by 1D10 plus your dexterity modifier (you may be able to make this the proficiency modifier .. the gloves are generally best for use with monks and high dex character who will start with. +2 or +3 and end up with a +5, but a strength based character is unlikely to also focus on dexterity ... and their proficiency will be comparable and also increase as they level up).  If you reduce the damage to 0 you can catch the ammunition or weapon if you have a free hand and if it's small enough to hold in a hand.
(this is just the gloves of missile snaring added onto a +1 battleaxe).

Give the item a cool name.  Give it an ability that can come in handy at least once every 5 sessions (you can build encounters with these things in mind).  Feel free to add descriptors to it.  A clap of thunder, or flash of light or something.  You're just adding drama and intensity with the description, not looking to do extra damage or status effects.

There's also no harm in just ... using an item directly from the DMG.  The players will still love it!