Here is my Plot Matrix: The Four Dragons
P.S. this is work in progress and may have some mistakes!
Black dragon, yellow dragon, long dragon, pearl dragon, people, emperor, and the mountain god.
Starving people because no rain.
Emperor says next week but forgets.
Emperor traps them under the mountain.
The dragons turn into rivers
And give people water.
The dragons become the rivers forever so people won't go without water again.