Jacopo de' Pazzi glitch
In the first clip i kill Jacopo normally, however while experimenting a bit more i accidentally killed him with my sword instead. His body lay there, i could loot him and carry his body but he was still whimpering away and i could not finish the mission. I guess this video could serve as a warning, dont try kill him with a weapon other than the hidden blade or this happens. I also have a few other instances where the game will not let you finish, i may put them all in one video later on
That's what you get when you make an old man suffer. It's strictly against Ezio's morals to make the dying suffer.
interesting find. i wonder if you still see him glow if you toss him in water or down a well.
Oh i forgot about a well. I couldnt remember where any water is on that level though. As you can see i am near Montergioni (sp?) as i tried to bring him to the villa as a trophy lol, unfortunately i could not go across the border, so i dumped him in the hay to see what would happen.
Tuscany [and Monteriggioni] are the only dry cities in the game, sadly we can't drown Jacopo 
this glitch is easy to duplicate. after you kill all of the guards around jacopo, draw out your sword and approach jacopo. look at the control hud - you should see "attack" change to "interact". if you press intereact, you'll get the normal story assassination of jacopo. just back up a little so that the hud changes back to "attack". now if you press attack, you'll get the non-story, sword-kill animation on jacopo. you can also pickpocket him before the non-story assassination, or, if you prefer, you can loot him after the non-story assassination.
once you've killed him with the sword, his body will be out of place. you can pick him up and carry him around. he can be thrown down a well, and you can see him light up the bottom of it. you'll find that "interact" shows up on the hud if you go back to Jacopo's original location - even tho hes not there anymore. its easy to find the spot by following the target icon on the minimap. press interact to assassinate the grass (seriously) and continue the story.
Ah so you can carry on. Anyway i think i did something wrong, i went to repeat it and i couldn't get it to work. I saw that it said interact and i realized it never said that before, so i stood back and tried attacking. Ezio just swung his sword over his body though, maybe because i was using the scimitar and its reach isnt long enough.
Anyway Ian i found a few more glitches relating to those videos you did on AC1 where you froze the assassination targets. You probably know this one as well, but you can freeze targets here too. However if you step in fron tof them, they will see you, but you can push them around from behind and they do nothing. I managed to push one target outside of his house in Seq 5 and kill him using a horse
ive tried a spear and sword with success. i also found that going back to the original spot and pressing interact typically teleports jacopo to that location for the assassination. the time that i said that ezio assassinates the grass was probably due to jacopos body being so far away that it wasnt modeled anymore. thus, there was no body to teleport back, and ezio is left assassinating nothing (ie grass).
jack, i think it is worthwhile to show a video on how to trigger this glitch. do you mind if i make this vid? or do you want to take it?
Go ahead, im not replaying the game to do that again.