Carmine Dragon

Carmine, or Encarmine Dragons, are a corrupted variant of the Dragon race known famously for its dark crimson color due to an over-exposure to "Death Magic". Contrary to popular belief, Carmine Dragons are actually not a separate sub-species of Dragons, rather these Dragons are born this way when a Dragon egg has become saturated by Shyish, the Wind of Death. When the unborn dragon is exposed to this, the death magic is gathered and magnified within the heart and soul of the dragon once it is born.

This variant of the Dragons is named appropriately for their strange and lustrous scales, supple as sin and harder than steel, which begins a deep ruby-red when they are young, darkening to a purple so deep as it be almost black as they age. Carmine Dragons are known famously as a race of sinister, clever and deadly creatures, often being symbolized as an omen of death and destruction to those that see them. Instead of breathing fire, Carmine Dragons unleashes a shockwave of Amethyst magic which rots and deteriorates any material into dust within a span of mere seconds.

These Dragons have been known to live within areas of the world where the Winds of Shyish is the most saturated. Such sites includes decaying swamps, ancient battlefields, and the ruins of fallen cities and kingdoms. Carmine Dragons feeds upon the Winds of Shyish with a monstrous appetite, and it is said that these Dragons have been known to hear the dark whispers of the dead when it sleeps in the darkness.

Although not inherently evil, these Dragons are nonetheless terrible when provoked, and would rarely submit itself to an alliance with any living creature, not even to others of his kind. It is only when this agreement serves a darker purpose, or when the rider is a wielder of dark arcane lore will it allow itself to be ridden into battle.

Source

 * Warhammer: Monstrous Arcanum -- pg 30