Talk:Game Updates/@comment-86.0.253.98-20121218111514/@comment-60.240.68.239-20121218125220

So Leap Year takes precedence over Blue Moon. To get a pair of LYDs, you had to be twice as lucky.
 * You can still get a second Blue Moon if you already have one, by breeding your first one with Equinox or another limited Moon-type.
 * For a Leap Year, you have to have two of them in order to breed another one.

Also bear in mind, there was no option for egg display when the LYD was out, so not everyone bothered to try for a second one.