Normally I use pre-published adventures either from Dungeon magazine or those written by WotC (and before that, TSR). However, I haven't been too impressed with the adventures that have come out for 4e.
One exception is the War of the Burning Sky series, but the drawback with that is that those adventures are part of an adventure path, and as such are a bit more difficult to shoehorn into other campaigns.
So I've decided I want to try my hand at writing my own adventure. However, I found that there isn't really a good source of information on how to go about doing that. Even the DMG and DMG2 I find aren't really good at giving a beginner ideas on how to come up with ideas for adventures and plot lines (although they are excellent sources of information for other aspects of adventures, especially for encounter design).
However, I have come across several webpages on the intertubes that are of good use:
1. The Big list of RPG Plots - This is fairly self explanatory, but is a good summary of RPG Adventure tropes.
2. Chatty DM Tropes - ChattyDM has a whole series of posts on using tropes for RPG ideas
3. Adventure Writing - Rich Redman had a couple of excellent posts in the d20 Modern archives on the WotC website. Included in this post is a great method of just coming up with ideas (thought webs and brain spiders).
4. TVTropes.org - Want to lose a couple of afternoons worth of time? It's very useful on getting ideas from movies, TV, literature and anime. It's worth reading even if you're not going to write adventures.
In Part 2, I will be discussing an interesting plot structure that most sucessful films uses, and how to apply it to RPG adventures.
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