It is brought in to beat Hyperion
I believe the answer is:
titan
'hyperion' is the definition.
(thesaurus)
'it is brought in to beat' is the wordplay.
'is brought in to' indicates putting letters inside.
'beat' becomes 'tan' (tan can mean to beat or hit).
'it' going inside 'tan' is 'TITAN'.
(Other definitions for titan that I've seen before include "One of the first pantheon of Greek deities" , "Huge(ly important) type" , "Taint in a mythical giant" , "immense figure" , "very big" .)