Note: Before you can use the ability to sweep with a long weapon, you must first train at the Combat Trainer in Monteriggioni. Press to speak to the trainer and select - Special Moves - Long Weapons
The sweep ability costs 10000 Florins
to learn so bear that in mind when you return to the Villa to learn it.
To sweep an enemy with a long weapon you need to target them with
then press and hold
to charge up the sweep, Ezio will spin the weapon around him until its behind him, you can then release
to sweep. If need be you can release early
Before you can even attempt this you will need to get a long weapon off one of the Seeker guards (Big guys with spears) You can either kill them and pick up their weapon off the floor with
or disarm them (Unarmed hold
as they attack)
This can be quite hard to get enough enemies hit with your sweep once you have your spear so you'll want to get a big group of guards on you before trying, for example get one group on you and block (
) and move around to gather more. Any populated city will work though I found Venice to be good for this.A lot of people suggest throwing down a smoke bomb but I had difficulty finding the spear again as you drop it throw the bomb, what I did was sweep once to get some on the floor and then charge up the sweep again and keep going until id got 5 at once.
Heres a video by PowerPyx