After the first battle what trophy does beowulf hang from the rafters of the hall

I belive it's the arm of Grendel

Explanation:

"Beowulf summons even greater strength and rips Grendel’s arm completely out of its socket. Fatally wounded, Grendel slinks back to his swampy home to die. Back in the mead-hall, Beowulf holds up his gory trophy in triumph. He proudly hangs the arm high on the wall of Heorot as proof of his victory."

the guest is my guess

reasoning from several particular examples to establish a general principle