Increase offer, partly, to reduce intensity (4,3)
I believe the answer is:
ease off
'reduce intensity' is the definition.
'ease off' can be an answer for 'reduce' (I've seen this before). I am not sure about the 'intensity' bit.
'increase offer partly' is the wordplay.
'partly' indicates a hidden word (part of the clue is used).
'EASE OFF' is hidden within 'increase offer'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for ease off that I've seen before include "Slow down" , "Let up" , "Slacken gradually" , "reduce tension" , "Moderate, slacken" .)