It all sounds possible enough, but I think the whole reef part is kind of stretching it. There's clearly some Norse references in the game though. Gjallarhorn means "Yelling Horn" in Norse mythology. [quote]In Norse mythology, Gjallarhorn (Old Norse "yelling horn"[1] or "the loud sounding horn"[2]) is a horn associated with the god Heimdallr and the wise being Mímir. Gjallarhorn is attested in the Poetic Edda, compiled in the 13th century from earlier traditional material, and the Prose Edda, written in the 13th century by Snorri Sturluson.[/quote] [quote]The single mention of Gjallarhorn by name occurs in the Poetic Edda poem Völuspá, wherein a völva foresees the events of Ragnarök and the role in which Heimdallr and Gjallarhorn will play at its onset; Heimdallr will raise his horn and blow loudly. Due to manuscript differences, translations of the stanza vary: Benjamin Thorpe translation: Mim's sons dance, but the central tree takes fire, at the resounding Giallar-horn. Loud blows Heimdall, his horn is raised; Odin speaks with Mim's head.[3] Henry Adams Bellows translation: Fast move the sons of Mim and fate Is heard in the note of the Gjallarhorn; Loud blows Heimdall, the horn is aloft, In fear quake all who on Hel-roads are.[4][/quote] Link to the source: https://en.wikipedia.org/wiki/Gjallarhorn