stupefying (adj.)

• analgesic
• anesthetic
• bloodcurdling
• deadening
• exceptional
• extraordinary
• fabulous
• hair-raising
• indescribable
• ineffable
• legendary
• marvelous
• mythical
• narcotic
• noteworthy
• numbing
• petrifying
• phenomenal
• portentous
• prodigious
• remarkable
• stunning
• stupendous
• terrifying
• terror
• unexampled
• unparalleled
• unprecedented
• unspeakable
• wonderful