The onion method: A method for creating dynamic in depth storylines
For the Mandalorian Wars mod i was working on, Secrets of the War, I wanted to do something to the plot that made it different, that kept the player guessing till the very end. This led me to come up with this system. The layers are not only for organization, but also how you introduce events and characters to the game.
The key to the Onion System is layering the plot.
On layer one is the obvious threat/conflict
Layer one focuses on what the player knows is happening.
Like in Secrets of the War, Layer one would be the Mandalorian Wars. Its obvious, everyone knows about it. It is the main event of the galaxy.
Now, peel away layer one and you get layer 2:
Layer 2 focuses on the Character himself, and his team. Layer 2 would include who his friends are, his allies, and his enemies, and character progression.
Also in the layer would be the PC's personality. His interests. Others interest in him. And how he builds trust with his party.
Pull away with that layer, and you get layer 3:
Layer three is the PC's backstory. What he was before the game started. What happened to him to put him where he is now. This is the most important layer of creating the PC. If you have a bad backstory, the character becomes uninteresting, and the game loses value. Now, it is ok to introduce the full backstory later in the game, as long as you have a backstory set up. It may be true, but not complete (as long as it seems complete, it may be totally bogus like the story of Revan. OR Kreia. It just needs to be revealed completely at one point or another.
Layer 4 it the background threat. This threat in itself is always present, but is only revealed in small quantities, or hinted. This is the layer that adds almost all depth to the plot, and it, in most cases, the most interesting part to the plot.
The plot to Secrets of the War, minus this Layer 4, is uninteresting. Its just the mandalorian war. Not too interesting. Now, add layer 4, and it becomes you are uncovering what unknown force is causing the war.
One of the most effective things to use in layer 4 is Manipulation. Some unseen force controlling the Main Threat from layer one makes the plot interesting, and comparable to religion in a way.
Layer 5 is pretty much the climax. The epic core. What all the other layers are feeding to. Peel away the layers to get to the core. What you want the most. This is when every unanswered question should be answered. If a sequel is planned, then this layer shouldn't actually answer all the questions. Leave one open, to keep people interested, or, create new ones!
That my friends, is the Onion Method. I hope it helps you guys when developing a future plot.
Disclaimer: I wrote this when I was 15 so it might not be so good but I believe it should help.
Disclaimer 2: I am NOT working on that mandalorian wars mod, though it is still my favorite plot I ever wrote..