God’s power comes from worship.

Worship has waned over the years with the Gods becoming more and more elusive, spending less time on Earth and more on Olympus.

The Titans have been watching and waiting. As the Gods power wanes, the prisons holding the Titans have started to crumble. (Tarturus) The Titans led by Cronus waited until the last of the prisons (that holding Cronus) collapsed. Cronus is released and quickly helps the lesser Titans. The gods finally leave Olympus to battle the Titans and one by one are captured and imprisoned themselves. Cronus tasks a Titan to guard each God in the prisons that used to hold the Titans themselves.

Over the years; jealous of humankind created by the Gods, the Titans rain havoc. Let loose of their prisons, the Titans destroy most of the great cities.

One of the original Gods and mother to the Titans Gaia watched the destruction. All destruction hurt Gaia. Although mother to the Titans, she had no sway and could only watch and subtly manipulate the Titans perceptions. She hid some of the humans from the Titans and convinced them that they had been eradicated. Having removed their main source of torment, the Titans went on to attacking each other. The Titans themselves hid from each other and only a handful would walk the Earth with no fear.

You are one of the remaining humans. A descendant of the Gods. You have risen as a leader to the people. Gaia visits you in a dream and reveals the secret of the Gods power - worship. With followers comes power, however you are constrained with what you can do with the imprisonment of the Gods. If you can release the Gods you can gain their power.  

You gain power from your worshippers and leave your hidden city to start to look for and unleash the Gods. You need to start off small and release the lesser Gods. With each God released you gain some small measure of power and ability..