Originally Posted by
inesat
Not sure if it's been mentioned before, but the 4 type combination with the fewest possible results I've found is Brightsteel and Nyx/Hercules. Only 8 possible outcomes. The "fails" aren't that bad either (longer ones are Blue Moon at 16 hours and Cloud at 17 hours - pretty good dragons to get as a "fail" if one doesn't have them already).
Before the Brightsteel was introduced, what I knew as best combo was Goodwitch/Metal with 9 possible results (coincidentally, this is how I got my precious Diamond).
I've noticed this being discussed on the wiki site, but I'm not registered to comment there yet.