[quote=@Lmpkio]
<Snipped quote by Lugubrious>

That's the thing, he wouldn't recognize or know what he did was that specifically. And being a character of Star Road, maybe it's a bit more feasible with the magic in some way?

Of course, I can always just have Geno "kill" him, have him hold on to his spirit core, eventually find his way to the Master of Masters and be told how to revive his friend from him. If you prefer the latter over the former, that's also completely fine.
[/quote]

I don't know what Star Road necessarily has to do with it. If that's relevant, please do explain. It is not at all feasible to create a Friend Heart accidentally.

You can indeed just have Geno "kill" him (or try to, anyway), though there's no known way to 'revive' a spirit that's lost its body as anything more than a Striker. Maybe it's in character for Geno, as a character centered around the idea of a higher authority, but so far I've seen a repeated theme: there being no other choice. If Geno doesn't somehow know how to save Mario, he can do other things besides just kill him. There are always other choices.