Prosecutors said Abedi had three makeshift knives during the initial assault, and then collected two more from his cell.
He appeared by video link from HMP Belmarsh flanked by five prison officers dressed in riot masks and protective body armour.
Abedi was dressed in a grey prison tracksuit.
He spoke to confirm his name and date of birth and also confirmed he did not want to be legally represented.
The accused also told the judge, Mrs Justice Cheema-Grub, that: “I don’t wanna attend anyway that’s what it is.”
He is due to stand trial from 18 January 2027.
Abedi was remanded in custody and will next appear at the Old Bailey on 30 January 2026.