Seven items of a kind read clockwise round the perimeter. In ten clues, cryptic indications omit reference to parts of answers; these parts must be highlighted, to reveal a definition of the perimeter items. Letters in corner squares and those adjacent to them could form WADERS, NOT OLD.
 

Across

 
11    Spirit and ogre in retreat talk dismally (5)
12    Stooge deserted after charge (4)
13    Revolutionary failure to capture current head (5)
14    Soul in small room following international game (7)
15    Insect holding attention around greenery in magnolia (10, hyphened)
17    Peasant, young, having day off (5)
20    Judge stopping...