RE: Dragon Breath Options
From: Aldred the GM

Dragon Breath

All the normal WFRP rules regarding Dragons and their breath weapons still apply, but with these options adapted from the WFB Beastiary.

Black or Smoke Dragons
      Personality - Torpid, slow moving, (the wisest of their kind)
      Alignment  -  Neutral
Once per turn can expel great quantities of thick, oily black smoke which serves to choke and asphyxiate opponents... Each character hit by this smoke (no dodge rolls), must make a WP test or begin choking and suffocating. (players take d10 minus their own T score, wounds to the Body, as their breathing passages become stifled). This damage heals at the rate of one point per hour, (or faster if you want) but if the players W reach zero, the player is either dead or unconscious (GM discretion).

Red Dragons or Fire Drakes
     Personality - Angry, short-tempered (the most hostile type)
     Alignment  - Evil
As Basic Dragon from WFRP, except all Dragons of this type have fire as a weapon, as opposed to the 50% listed.

Green or Corrosive Dragons
       Personality - cunning, devious, (the cleverest of Dragon kind)
       Alignment   -  Neutral or Evil
Belch sickly green and highly acidic fumes. Anyone hit by these fumes must take a S 3 hit to any exposed skin area and make a successful WP test or all percentage characteristics are halved for the duration of contact and a further 1d6 turns after escaping the corrosive fumes due to watery eyes, burning, itching skin, etc.

Blue Dragons or Storm Drakes
     Personality - Varies (sometimes calm, sometimes the weather)
     Alignment   - Varies from mood to mood....
Spit (once per turn) 1d6 forks of deadly lightning. Each bolt has a 24 yard range and at the Dragon's discretion, can seek out a different (or the same) opponent. Each bolt has a 50% chance of hitting an opponent. If it fails, then the lightning bolt grounds into the earth and does no damage...but, if the bolt successfully hits it does one S 6 hit (armor and T work as normal) and gets another 50% chance to see if it leaps to another target within 24 yards of the original one (where it does another S 6 hit, and maybe leaps again). These lightning bolts will bounce around until they ground. Players may attempt to use the Dodge Blow skill...successful tests will halve the damage sustained.

The Blue Dragon in never the target of these bolts, which has many convinced that somehow the creature can guide or control these missiles...

White Wyrms or Snow Dragons
     Personality - Regal, refined (the most noble of their ilk)
       Alignment   - Good
Breathe a sub-zero mist that chills men to their bones and numbs the mind. Anyone caught in this icy cloud, sustains one S 5 hit from the bone jarring cold, and must make a successful WP test or they are frozen to the spot and have their I halved and t heir M reduced to zero for 1d6 turns while they thaw out...They may fight and parry as normal, but due to numbness in their extremities, suffer the effects of Fumbles on any doubles rolled, even if under the players WS. (i.e. 11, 22, 33,44, 55, 66, etc .)

And my own creation....

Psychedelic Dragons or Dream Drakes

     Personality - Any
       Alignment   - Chaotic
Are often mistaken for White Dragons....their hide being a pearlescent hue with scales which reflect pinkish or blue-green in varying light...their breath is like a rainbow mist which seems to have no effect on people....(anyone hit must make a WP test o r suffer d6 insanity points). 50% of these mysterious creatures can cast the BM spell Steal Mind without components or magic points thrice per day, while all are able to cast the Petty Spell Sleep at will.