I currently have a problem designing a weapon type to be different more than the model, however, I have no idea how to approach this.

In my game, I have a weapon type, likes sword, axe, staff, mace, spear, knuckle, bow, xbow, etc... most are using same swing animation except spear, knuckle, bow, and xbow and hit sound effect are all different, while stats (damage, range, speed, damage type) being randomly assigned, also, all my attack only hit 1 target, never cleave through target.

Which create a problem that makes weapon type being the same, so I want to make each weapon type gives a different play style or, at least, something different than the others without forced that weapon type to specified roles (except melee or ranged), which may further create potential balance issues.

Most game I found either forced damage type, giving stats boost to specified weapon type or perks, however, I don't think it will go well with my game.

Any idea?

One pretty standard way to differentiate the weapon types is by assigning them damage types like "cutting" "stabbing" "blunt trauma". From there you can have armor (or enemies) that have different armor stats vs different damage styles.

You could also keep the random stats but influence them by weapon type, say a random dagger always gets a boost to speed while a warhammer also ways gets a speed penalty but a damage bonus on its randomly rolled stats.

I am suprised there are not more comments on this... Personally, I think you are limiting yourself by not allowing weapons to affect multiple characters, one of the easiest methods of displaying difference between weapons would be attack patterns. *BUT* there are still plenty of other good ways. The Slashing/Bludgeoning/Piercing attack types is a good start. Other possible methods: If range is currently binary (Melee/ranged) you could split it into more ranges... short range (daggers), Melee range (swords), Reach (Spears), Ranged (XBow, etc). You give each weapon type a specific effect... Knockback on war hammers, Sunder Armor on Battle Axes, Bleed on daggers, Trip on whips, Disarm on... uh... you know... the pointy things made to disarm people, etc...

Interesting topic!

As far as MHO goes is there a chance you might be approaching the issue bottom up rather than top down?

What I'm thinking is that rather than adding several different stats which would give new dimensions to gameplay, some of which might fit some of which might not, would it not be helpful to turn the problem around?

That is, what kind of gameplay difference would you like to achieve? This would then directly transform into suitable division of weapon types/effects.

Few (completely random) examples:

1) "Geez, fighting multiple enemies are really tricky right now!" => Some weapons might have area effects to combar large enemy groups => area damage could be suitable stat for certain types

2) "Wouldnt it be fun if some enemies had really tough armour?" => Some weapon types should be better suited for combating these enemies => armour pierce might be good for some weapon types

3) "Man, these ranged enemies have knockback which makes them difficult to approach by the player!" => Some weapon types might help as gap closer => certain weapon types add forward momentum

Etc... etc... etc..

Bottom up could of-course be completely viable as well but in my own opinion I would try to look at the issue the other way around and let the gameplay you are after help chisel out which weapon affects you could add to the game

Well, just my few cents

I agree with BG109. Rather than starting with all your weapon types beforehand, make some prototypes and find out interesting and fun challenges that could be added to your combat system. For example, you might find that its fun to have a nonspecific weapon whose playstyle is based around timing, be it parrying or dodging. Then, make a suitable weapon for this playstyle. For this hypothetical example, a rapier or sword would probably be best as they are probably the weapon associated the most with parrying.

Anyway, just play around with prototypes to start off with no specific weapon in mind. Also, unless the theme of your game is realistic fantasy, don't be afraid to create some kind of crazy weapon if a fun playstyle doesn't fit with a real world weapon.