“Watchtower is one of the more elusive immortals who we will be covering here. His infrequent appearances are invariably brief, mostly confined to the corners of photographs and glimpses barely lasting seconds, and he rarely speaks to anyone when he does appear. He does, however, have an extraordinary knack for acquiring some of the world's most valuable artefacts.

“What he does with these artefacts is both unpredictable and variable. Some reappear soon afterwards, in unusual or interesting locations around the world. Others find their way to where they are most useful, often behind locked doors and ultra-tight security. Others still are never seen again, and what Watchtower does with these artefacts is entirely unknown.

“Comparing photos which feature Watchtower suggest that he is ageing, but only incredibly slowly. Given how invulnerable he is when he is intangible, it is likely that Watchtower will be the last Immortal in existence, and indeed he might never die.”

- “On Immortals,” 2487, Anon