Dragon Rod (3.5e Equipment)
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Dragon Rod: Long ago, a wizard made the Dragon Rod to demonstrate that his power stood at the level of the gods. The gods responded by destroying him. The Dragon Staff that he created was lost.
The Dragon Rod combines two dragon eggs into one, creating a hatchling of hybrid lineage. To activate this rod, the wielder must expend one 7th level or higher spell slot and have two viable, unhatched Dragon eggs.
All dragons hate this rod, viewing it as blasphemous. Evil dragons seek to kill the wielder and destroy the staff. Good dragons seek to determine whether the current owner has used the staff. If the current owner has not used it, they seek to reason or bargain with her, to save her from her own folly. If this is not successful, they resort to violence. Should the wielder have used the staff, then good dragons feel morally compelled to destroy the wielder for their blasphemy.
The only known dragon type made from this process is the Shadowfire Dragon, made from the eggs of a Shadow Dragon and a lesser dragon, the Hellfire wyrm.
It is also of note that dragons created by the rod, and all descendants thereof, appear to feel a form of loyalty to the wielder of the staff as a Gold Dragon to it's parents, with some reports saying it mirrors more closely the relationship between a vampire and their sire.