KUALA LUMPUR—Kelana Indra Sakti is one of Malaysia’s most successful shamans. Framed testimonials from his customers hang from his office walls. In the driveway of his house he keeps a stretch Mercedes-Benz limousine given to him by a grateful client. His name, meaning “Adventurer, Heavenly Magic,” was bestowed on him by one of Malaysia’s wealthy sultans.

Lately, though, Mr. Kelana has supplemented his consultations with readings from the Quran.

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