Strange Frontier
Although Taylor again played most of the instruments himself ( drums , guitars , bass and keyboards ) and did most of the vocals , there were some occasional cameos by producer David Richards ( on synths and piano ) , Status Quo member Rick Parfitt ( on rhythm guitar ) and Queen's bass guitarist John Deacon ( on bass and mixing ) , Brian May ( rhythm guitar on "Man on Fire" ) and Freddie Mercury ( additional keyboards , and it is rumoured Mercury did backing vocals on "Killing Time" , although this is speculative ) . 
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