Talk:Halloween Princess/@comment-27.77.159.97-20151026081850/@comment-27059222-20151026235127

You need to feed 4 copies of the same card to reach the limit. (So 5 in total, 1 for the original, 4 copies for feeding)

Since only 4 of this particular card can be obtained via the exchange shop, you need to get lucky and get 1 drop from either the 30 AP or 40 AP quest