More bloody time up in Kings (5)
I believe the answer is:
rarer
'more bloody' is the definition.
Both the answer and definition are comparative adjectives. Perhaps you can see an association between them that I don't see?
'time up in kings' is the wordplay.
'time' becomes 'era' (an era is a period of time).
'up' is a reversal indicator (in down clue: letters go upwards).
'in' is an insertion indicator.
'kings' becomes 'RR' (abbreviation for rex - 'king' in Latin - repeated).
'era' backwards is 'are'.
'are' going within 'rr' is 'RARER'.
Can you help me to learn more?
(Other definitions for rarer that I've seen before include "(Of meat) less cooked" , "Stranger" , "More unusual" , "less easy to find" , "Comparatively sparse" .)