Because of its aquatic nature and close resemblance to Gigan, Seagan's name may come from combining the word "sea" with Gigan's name.
Seagan resembles Gigan, sporting scythe hands, spikes on its backs, and a similarly-shaped head.
Seagan is the result of an alien substance mutating zooplankton.
Seagan has the ability to spray poisonous fluid from his mouth and fire energy blasts from his tail.
Seagan info from Godzilla 1954-1999 Super Complete Works
This is a list of references for Seagan. These citations are used to identify the reliable sources on which this article is based. These references appear inside articles in the form of superscript numbers, which look like this: 
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