"Execrable," as worded above.
The guy is taught a cellular regeneration technique, then teaches himself to shape shift, including clothes.
Kirk is bringing magic medicine that will cure all mental illness forever.
While on a penal colony, the "madman" invents the most powerful explosive ever. This is like a '60s comic book. All we need is Bat-Mite.
"Madman" also has found the time and talent to modify the neural neutralizer into a painomatic chair.
Plus you have crazed-eyed (nonfat, btw) Craig doing a parody of a madwoman, "He is my lover and I must kill him."
Extended, too-long dance sequence. And coronation ceremony.
I often defend S3 being as good as S2, but this is one of the ones that justifies S3's reputation for camp/lameness.