Board Thread:General Discussion/@comment-24471533-20140126214248/@comment-24145588-20140206175430

I'm on the fence about the level/happiness factor. Like PMMama, I've had most of my success with higher-level and happier monsters, but, as she observed, I've also had many more tries with them. I use low-level monsters to breed only in a few cases (e.g., I keep a level 4 Tweedle in the shed on my Water Island, just for breeding), and usually don't do as well with them.

I've also had no success trying to breed a Grumpyre, and I'm starting to wonder if I should bite the (gold) bullet and get my Deedges up from 50% happiness.

On the other hand, I have to remember the fundamental fact -- randomness is exactly that: random. I have a really, really small sample of low-level monster breeding, and vastly skewed results in favor of using high-level monsters. And although my 80-plus attempts at breeding a Grumpyre feels like a lot, statistically it's well within the expected range.

So I'll do what I expect most players do: hedge my bets, and keep using the highest level and happiest monsters to breed. I want them high and happy (grin) anyway, and it certainly can't hurt their breeding chances, so it seems like a good idea.