Game over? Everybody hides outside (3,5)
I believe the answer is:
all fours
'game' is the definition.
(all fours is a kind of game)
'over? everybody hides outside' is the wordplay.
'over?' is a charade indicator (letters next to each other).
'everybody' becomes 'all' (all people).
'hides outside' becomes 'fours' (I can't justify this - if you can you should give a lot more credence to this answer).
'all' put next to 'fours' is 'ALL-FOURS'.
Can you help me to learn more?
(Other definitions for all fours that I've seen before include "steady par round?" , "Both arms and legs" , "Walking on them, one is on hands and knees" , "Bear thus to make progress" , "Hands and feet" .)