Looking at the weapons, I see very few deal curse. They're far out numbered by piercing, normal, and elemental. And there are even fewer weapons that deal Curse as an effect. In fact, the only weapons that even deal curse are the Faust, and the Gran Faust. I know someone is bound to half-read this and say "this is a bad idea, this will mess up the game!!!!!! noooooooooo!", but if you wouldn't mind actually reading this fully, understanding the points I am making, and making an intelligent, well-thought-out comment on this, I would greatly appreciate it.

Realizing this extreme lack of curse-dealing weapons, I decided to think of a possible suggestion. I came to the conclusion that the Faust/Gran Faust is a pretty good curse sword as it is, so just adding another curse sword would be quite senseless unless the Nightblade/Silent Nightblade/Acheron was being considered in that factor as being able to deal curse. So I decided to just go with a gun for the idea (most people carry a sword and gun, so being able to have a curse loadout like that would be nice), and so then it came down to deciding what gun should have a curse variant. I didn't want to just pick a random shadow gun and make it have the ability to deal curse, because people don't really like having their weapons changed a lot. So I naturally just looked for a gun that did not already have a shadow variant, was a good type of gun, and would work well with Shadow and Curse without being some insanely overpowered, yet not underpowered gun.

It eventually lead to me picking the autogun for this, since it is unique compared to the other guns available, which have very little difference from one another as far as how they function (yes, their stats are all different, but the actual FUNCTION is not). The autogun - despite how unique it is compared to the other weapons - has but 3 versions. One that deals fire and normal damage, one that deals piercing exclusively, and one that deals poison and piercing. It needed another line in my opinion, and so here it goes.

Alchemy path:

Autogun > Dark Needle > Shadow Needle > Cursed Needle

Pictures (taken from wiki and edited by me) :

Icon for the shadow variant of the autogun: http://i1087.photobucket.com/albums/j469/Speedran/Spiral%20Knights/shado...

Dark Needle: http://i1087.photobucket.com/albums/j469/Speedran/Spiral%20Knights/dark_...

Shadow Needle: http://i1087.photobucket.com/albums/j469/Speedran/Spiral%20Knights/shado...

Cursed Needle stats: http://i1087.photobucket.com/albums/j469/Speedran/Spiral%20Knights/curse...

This is actually not overpowered at all. For one, the chance of it actually dealing curse is low, and before someone cries out "SHADOW IS OVERPOWERED! NO! NO!" I would like to point out that Shadow is just as good as Piercing or Elemental, depending on the enemy you're fighting, so if you go "THIS IS OP!" please do go hate on the Blitz Needle, and Plaque Needle as well. Why curse you might ask? Simple. It, just like all other effects, is an effect. A useful one no doubt, but from what I've seen in real gameplay, Curse is not so absurdly powerful that it must be shadowed (pun not intended) to such a point that only two weapons can deal it. Also, when fighting the Jelly King, Curse is almost vital, and if you run out of curse vials, your only solution is going to be a weapon that deals curse. And the Faust/Gran Faust's charge attack can curse you for 40 seconds, and the basic attack (which can deal curse on the second swing) rarely deals curse, and deals much less damage than charging. This is where you could use a weapon like the Cursed Needle.

And before someone else shouts out "THIS WILL RUIN THE REASON TO GET THE BLITZ OR PLAGUE, PLEASE!!! NO!!!!", I would like to also note that it deals Shadow. That meaning, it's going to be potentially useless against enemies such as fiend and undead when compared to the Blitz and Plague, evened out when fighting construct, and so on. and so, Blitz and Plague would not lose popularity, nor would any other gun. The Cursed Needle is not the ultimate gun - it's just a well-needed addition to both the autogun line, and the very few curse-dealing weapons. It would not unbalance gameplay, it would not do anything bad at all if it were added, unless you count there finally being a new curse weapon as a bad thing.

EDIT: Forgot to add this part: This gun can only deal curse with it's final shot. For example:

Basic attack (For the Cursed Needle):

Attack #1: launches 6 bursts that do not deal curse, but deal shadow damage.

Attack #2: launches 6 bursts again that do not deal curse in the exception of the last bullet, which has a fair chance of causing curse.

Charge attack (Cursed Needle):

The gun fires 15 bursts, with the final burst being capable of dealing curse.
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