Sentence:  ... I was suddenly awakened by a savage looking fellow standing close to my bedside, ordering me and my companion to leave our bed forthwith or suffer the consequences; at the same time using the most blasphemous language, and uttering the most hideous oaths imaginable, while <WSD>fiendishly</WSD> striking his huge fists in close proximity to my face. 
Meaning of the word marked with <WSD> tags:  In a fiendish manner; evilly, wickedly.