What would you call death by magnetar?
Nobody has ever needed such a word, and it doesn't exist.
&quot;Spaghetification&quot; is, of course, a joke word, but each time you make a new joke based off an old one, the less funny it becomes.
If you just want a (poor) joke:  Teslascind

In order to capture @pela's ephemeral comment in a more durable post:

Magnetaaarrgh!