oddly — differing in nature from what is ordinary, usual, or expected: an odd choice.
abnormally — not normal, average, typical, or usual; deviating from a standard: abnormal powers of concentration; an abnormal amount of snow; abnormal behavior.
amazingly — causing great surprise or sudden wonder.
rarely — on rare occasions; infrequently; seldom: I'm rarely late for appointments.
remarkably — notably or conspicuously unusual; extraordinary: a remarkable change.
startlingly — creating sudden alarm, surprise, or wonder; astonishing.
surprisingly — causing surprise, wonder, or astonishment.
uncommonly — in an uncommon or unusual manner or degree.
uniquely — existing as the only one or as the sole example; single; solitary in type or characteristics: a unique copy of an ancient manuscript.
queerly — strange or odd from a conventional viewpoint; unusually different; singular: a queer notion of justice.
astonishingly — causing astonishment or surprise; amazing: an astonishing victory; an astonishing remark.
exceptionally — To a greater degree than normal; unusually.
fantastically — conceived or appearing as if conceived by an unrestrained imagination; odd and remarkable; bizarre; grotesque: fantastic rock formations; fantastic designs.
indescribably — not describable; too extraordinary for description: a scene of indescribable confusion; indescribable euphoria.
unfamiliar — not familiar; not acquainted with or conversant about: to be unfamiliar with a subject.
unnaturally — contrary to the laws or course of nature.