Board Thread:Questions and Answers/@comment-24.100.149.16-20130214003536/@comment-7486518-20130412015254

The only way to get a Passion is:

1) Left Heart + Right Heart

OR

2) Diamond + Diamond

That's it  =( You'll still have your Left Heart Dragon if you already have one. When they "take away" a dragon, it's just to remove it from breeding possibilities. Else everyone would be very very mad about past dragons =p