by sigmazero13
As far as I'm aware, there is no "second edition", just a revised edition. However, there are a lot of people who are referring to the revised edition as the second edition. Just out of curiosity, where did you see reference to a "second edition"?As for the difference, the games are pretty much the same. The revised edition has some rule changes; on paper, they are fairly minor (although they can have some wider strategy impacts, especially the change to victory conditions). The other big difference is the Revised edition comes in a smaller box; a couple of the bigger map pieces in the Revised edition come in two halves that are puzzle-fit together. This has no gameplay effect, though. The revised edition uses thinner cardboard for the race sheets, as well, but that's just aesthetic and doesn't affect gameplay.
I personally like the original-version Coffin box. If you were to get that one, the only thing you'd "need" to play the revised edition is to download and print the rules and the "changes" document.