A quasi-deity once meant that a being was immortal and superior to any mortal creature. A quasi-deity's mundane movement speed was superior to that of a mortal creature. Some quasi-deities could not grant spells. True dragons who mastered the art of a dragon ascendant represented an exception, for they could grant spells to those who dedicated themselves to them. A quasi-deity was completely immune to every attempt to tamper with its mind, sap its vitality, or force it into a different form. It had a strong defense against magic but only a limited defense against heat. Weapons not enchanted with magic of an epic scope could not hurt a quasi-deity without problems. These defenses against magic, heat, and non-magical physical attacks grew stronger as a deity rose in rank. After the events of the Second Sundering, the Dead Three also became quasi-deities, due to their lack of intent to follow Ao's new rules regarding mortal interaction.
Quasi-deities were subdivided in three categories:
- Creatures born of the union between a deity and a mortal. This was the weakest form of quasi-deity.
- These creatures were created by deities. Titans could come into being deliberately, such as through being forged or willed into existence by a deity or as the offspring of two deities; or unwittingly, such as the blood spilled by a deity.
- Deities who had lost their followers and became nearly powerless. They were regarded as "dead" by mortals, but could still be contacted and still possessed some latent power.
If a quasi-deity amassed a sufficiently high number of followers, it could then ascend to true godhood.
- Tchazzar was a fully developed dragon ascendant who granted spells to his own church.
- The Dead Three: Bane, Bhaal, and Myrkul.
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