Anyone had a glitch where the guy you play as (Altair) is cloned? This happened to me during the assassination of the guy you fight at the start.
I got to control both at the same time! and i could accidentaly hurt myself and my clone! though i never got to use him in combat unfortunately (game froze after 3mins of awesomeness).
before this happened, alot of other glitched happened before that.
I fell through the floor and fell for a while then i died...while still falling - i fell past some water

The enemies that are supposed to ambush me never did - the only ones i got to fight were the ones already walking around after the second structure
and when i respawned i had two altairs doing the exact same thing and mirroring each other when i aim at the clone.
Also, i replayed that level.
THis is the coolest glitch
ever
P.S sorry but i dont have proof. But i promise you all this is true