More bloody rivers engulf barrier, sporadically lapsing (5)
I believe the answer is:
rarer
'rivers engulf barrier sporadically lapsing' is the definition.
I can't judge whether this definition defines the answer.
'more bloody' is the wordplay.
I cannot really understand how this works, but
'bloody' could be 'rare' (I've seen this in another clue) and 'rare' is found within the answer.
A single letter 'r' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for rarer that I've seen before include "even less common" , "Less frequent" , "steak may be wanted thus?" , "More unusual" , "less easy to find" .)