New branch of force facing initially serious riot (8)
I believe the answer is:
offshoot
'new branch' is the definition.
(I've seen this before)
'of force facing initially serious riot' is the wordplay.
'of' becomes 'o''.
'force facing' becomes 'ff' (this could be a standard abbreviation of which I'm unaware).
'initially' says to take the initial letters.
'riot' becomes 'hoot' (I've seen this in another clue).
The first letter of 'serious' is 's'.
'o'+'ff'+'s'+'hoot'='OFFSHOOT'
Can you help me to learn more?
(Other definitions for offshoot that I've seen before include "Branch, derivative" , "Branch; spin-off" , "Subsidiary product or branch" , "Side growth" , "sequel?" .)