The triggering of Murf’s first stage metamorphosis in ‘Let Sleeping Borg Lie’ which caused Murf to form a Chrysalis/Cocoon may be a result of being around the Diviner’s weapon for so long now. Murf may quite simply be evolving to instinctively consume this weapon, a triggered process by proximity. Murf’s form in ‘Crossroads’ could be one of the intermediary stages, preparing for a fulfilling meal which Murf is not quite ready for yet.
Murf could consume the Diviner’s weapon just before it is about to destroy Janeway/Starfleet in a final act of sacrifice and this leads to Murf exploding, but unexpectedly from the dust a *beautiful* Chrystalline Entity appears, just like how the debris from the Genesis weapon and Mutara Nebula formed the Genesis Planet in TWOK; they could even use similar music for dramatic effect. A phoenix rising from the flames. For Murf’s final metamorphosis their species may need a sudden burst of ‘massive’ energy in order to ‘crystallize’. Melanoid Slime Worm’s may usually gather at star’s before they go supernova in order to complete this process, migrating en mass from around the galaxy instinctively. It would be a bit like the opposite of what Gumtu did in the The Next Generation episode ‘Tinman’ where the space faring alien ‘entity’, which was the last of it’s kind, went to a supernova to die as a part of it’s lifecycle. Not many Slime Worm’s make this journey though as they lack warp drive or tech to do so which makes the actual final evolution of Melanoid’s very rare. People usually laugh at this species though thinking that they are slow, unintelligent and a useless slimy waste of space… so some bullies may use their name as an insult against others. If only the bullies knew the truth though… I would hate for the Melanoid’s final form to have to come back to find them all… hehe
Of course, Crystalline Entity Murf could no longer stay with the Prodigy crew, so there would be a very sad moment as Murf leaves in to the unknown, with music like at the end of Encounter at Farpoint when the two jellyfish aliens hold hands and fly off together.
Alternatively, perhaps this is a controlled crystallization which can slowly wear off, only triggered occasionally as a deus ex machina as needed in a story… a bit like how some Pokémon have an all powerful ‘mega evolution’ which only lasts a few hours. Eventually though, Murf *will* get stuck in the final chrystalline form… for Murf’s future is written as indelibly as Captain Pike’s.
