User blog comment:Ichigostop/Marco's ability is unique?! yeah right../@comment-1595565-20110428201945/@comment-71.141.250.148-20110429014053

Unique means "one of a kind" like all other devil fruits. Mythical Zoan devil fruits are not in fact unique because there is at least one other known Mythical Zoan. So the Mera Mera fruit is unique amongst logia, but there are multiple logia.