The more villagers and relics you have the more divine energy you will have. The last three god powers are revive (requires 600 energy), grant youth (requires 700 energy) and earthquake (requires 800 energy). The earthquake is the only way to convert the red and yellow masked heathens. Revive will allow you to bring a dead villager back to life. And Grant Youth will allow you to make an adult/elderly person into a child. The person will go back to the age of 5 no matter how old he/she is.

Wait how could you have finished the game if you don't have the power revive? You need it to finish the lake puzzle.