It downplays setter getting eaten by 50 bears (7)
I believe the answer is:
litotes
'it downplays' is the definition.
(rhetorical device of ironic understatement)
'setter getting eaten by 50 bears' is the wordplay.
'setter' becomes 'I' (the person that set the crossword).
'getting eaten by' indicates putting letters inside.
's0' becomes 'l' (Roman numeral).
'bears' becomes 'totes' (I've seen this before).
'l'+'totes'='ltotes'
'i' inserted into 'ltotes' is 'LITOTES'.
(Other definitions for litotes that I've seen before include "Ironical understatement (grammar)" , "An ironic understatement about toilets" , "not exactly truthful, for example" , "No exaggeration" , "Town of N. Norway" .)