I was nominated flyest so you'll see I'll take us higher, the defiant one
The phoenix from the fire, hell mouth leviathan
Only get killed at the end of time so I'm buying some
Jean, not for the first time, uses imagery around the mythical bird the phoenix, thus tying in both to the legend and to her own rap name. The X-Men character Jean Grey, from whom the rapper took her moniker, herself died and was reborn as a character called Phoenix. The phoenix is in a sense immortal, living for 500 to 1,000 years before burning up. Out of the ashes arises a new, young phoenix, reborn
Notice, even in the midst of all the mythological references, how Jean has time to pun on “flyest” and the idiom of “buying time”. Also, “only get killed at the end of time” is an apt description of what happens to video game characters
“Hell mouth” could be referencing one of two things (or both): 1. some medieval and renaissance art depicts the entrance to Hell as being the mouth of a giant beast and 2. in the TV series Buffy The Vampire Slayer, the fictional town of Sunnydale was built over a Hellmouth, a place where all sorts of (bad) supernatural s**t happens.
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