Subtheme

A Subtheme is a subset of a parent theme. For example Blacktron is considered a subtheme of Space and Sea Monkeys is considered a Fan developed subtheme of Aquazone.

Subthemes as a classification scheme, are subject to interpretation and dispute as LEGO does not seem to respect the historical subtheming nor do they brand their sets consistently. Re-use of names and artwork is idiosyncratic and sometimes appears to be used only to reference nostalgia amongst older fans.

The most egregious instance is in the longest-running and largest theme: town. While the number of overlapping and conflicting theme names in Town is huge, Space and Castle have had similar issues over the years.

This creates some confusion amongst fans but even more so amongst the sub-group of collectors for whom classification is essential if they are to posses complete collections.