Detective Comics #304

Matt Hagen breaks jail again and uses his powers as Clayface to impersonate wealthy men in order to gain information for future crimes, which brings him into renewed conflict with Batman and Robin. However, Clayface’s powers are limited by time, and in order to keep working, Hagen takes a sample of the mysterious pool and starts investigating the element with a scientist he has kidnapped. Batman obsesses over Clayface, and his investigation leads him to the criminal’s secret hideout, where he learns of the chemical sample. Batman incorporates the chemical sample into a freezing gun, and with the weapon he is able to stop Clayface.