The Legend of Gulltown: the Ocean (Vol. 142)

Summary

In a floating island suspended in a sea of violet clouds, a street-smart thief searching for a legendary key discovers a velvet black thread that absorbs all light around it that could summon a celestial leviathan that lives within the deep ocean. Pursued by a mechanical colossus awakened from its centuries-long sleep, they must race against time before the tolling of the midnight bell at winter solstice.