Physically attack iron clad monster with purpose (3,5)
I believe the answer is:
use force
'physically attack' is the definition.
I don't know anything about this answer so I cannot tell whether this works.
'iron clad monster with purpose' is the wordplay.
'iron' becomes 'Fe' (chemical symbol for iron).
'clad' is an insertion indicator (clad can mean covered by).
'monster' becomes 'orc' (fantasy creature).
'with' means one lot of letters go next to another.
'purpose' becomes 'use' (synonyms).
'fe' placed around 'orc' is 'force'.
'force' after 'use' is 'USE FORCE'.
Can you help me to learn more?
(Other definitions for use force that I've seen before include "Employ compulsion" , "Employ coercion to cure foes" .)