How to Wield the Papal Staff Against Rodrigo Borgia
Okay, so I' don't have any proof to show you but please take my word for it. After watching Ianxo4's video on poisoning Rodrigo and using the Papal Staff I decided to replay the game to see if I could get similar results. I wondered whether there was a way to force Rodrigo to drop the staff and came up with the conclusion to use a heavy weapon's special move. Thanks Ianxo4 for the inspiration
Here's how to do it, first of all get through to the part in Rome where you first see the Brutes then disarm or kill them and take their weapon. Get rid of the enemies and proceed through the hallway CAREFULLY without being desync. When you get to the room where you can here Rodrigo's voice jump to the wood platform and then to the wooden stand with the tightrope. Cross through to the final wood platform and position yourself to jump down near Rodrigo make sure you don't drop the heavy weapon and kill him with the heavy weapon.
A bug occurs in the cutscene where he blows you back with the staff, since Ezio held the Axe/Claymore he drops it in the cutscene but remains in the same place without being blasted back. Pick up the Axe/Claymore as soon as the fight starts and use the fully charged special move to disarm Rodrigo. There you go you can now pick up the staff and beat him to death with it. The next cutscene where he stabs Ezio has another bug; Rodrigo is carrying an invisible staff 
lol. You can pick up the staff after you regain control of Ezio but you still drop it in the final fight sucks 
Okay, so your saying that actually happened when you played the game like that, or that might happen if someone plays the game like that? That's definitely worth looking into. 
Another thing, after the first scene when all the people in the room die can Ezio pick up any of the brutes weapons?
Okay, so your saying that actually happened when you played the game like that, or that might happen if someone plays the game like that? That's definitely worth looking into.
If I remember correctly, I tried to do that, but the weapons had disappeared.
"When you have to kill a man, it costs nothing to be polite."- Winston Churchhill
"Kill a man, and you are an assassin. Kill millions of men, and you are a conqueror. Kill everyone, and you
When I first saw the title to this forum, I thought I was going to have to say "Ian already did that a long time ago. HAR HAR!"
Great job. 
Yeah it happens when you play the game like that, unfortunately you can't pick up the brutes weapons after the scene where everyone is knocked unconscious. You have to take a brutes weapon from outside the Sistine chapel bring it into to the chapel and maul Rodrigo with it. After the scene where Rodrigo uses the staff to make everyone unconscious you can't pick up any of the Brutes' weapons because they are removed from the game but the weapon you carried inside after attacking the pope remains modeled so you can pick up the axe/claymore you brought in again. Then you can use it to disarm him with the special while he is occupied with the clones.
very nice! i'm really impressed!
I' don't have any proof to show you but please take my word for it.
I have personally confirmed it and plan to document it on video. It works just as Kaiyui says.
Jump to the wood platform and then to the wooden stand with the tightrope.
This part is tricky to do without dropping the heavy weapon. You can Run but not Sprint while carrying a disarmed weapon. To perform these jumps: run, aim and just tap the Legs button. If you hold down the Legs button for a free-running sequence, you will lose the weapon.
Jump down near Rodrigo make sure you don't drop the heavy weapon and kill him with the heavy weapon.
You have to do this quickly before being detected! I found it best to target lock Rodrigo before jumping.
Front paged.
Thanks Stabguy for taking your time to checking it, also I found an easier way to do this. The game only stops modeling weapons held by the brutes after the first fight with Rodrigo starts. If you carry an axe in or instead if you were detected on the way in to the chapel you lose the opportunity to bring an axe in because the only brutes left are guarding Rodrigo, but lure a brute to the back of the chapel poison him and punch him right away this counts as unarmed knocked and will not alert the other brutes but MAKE sure the monks aren't to close or they'll start a commotion. The poison and punch seems to work in every situation where you can't kill a target (works in the unarmed carnival fight against Dante too) and it won't alert other guard like how a regular poison would when the victim dies since they don't die due to the punch. The brute that was poison and punched will sometimes drop the weapon through the floor so rinse and repeat until you can pick up a heavy weapon.
Walk through the crowd to the very front and drop your axe at the front where the first row of monks are. I've tried every possible way to hit Rodrigo with the heavy without desyncing from ground level with no success. Instead after dropping the weapon just run up to him switch to the hidden blade and assassinate him. After the cutscene your axe/claymore is still modeled and you can pick it up to disarm Rodrigo without all the hard trouble of the previous method. Thanks again Stabguy for looking into this and making a documentary.