The expert realism guide will cover everything from normal difficulty to expert realism. Going to talk about weapons, strategy, easier maps to get the achievement on, witches, crescendos where the horde ends and those that don't, finales, etc.
Its not going to cover every map, unless you want it to.
You will need to have completed at least 10 expert realism maps to join in making the guide. It is best if you have tried speed running in expert realism before, because that is a topic I want to cover. Also you can be the creator of the guide if you have more to contribute, its all for the community anyway.