Perform the following tasks in the Mercenary Guild Challenges:

Send Mercenary groups to attack guards ten times.
Kill five guards by throwing them into scaffolds.
Kill twenty five Brutes.
Kill twenty five Papal Guards.
Kill twenty five guards while you ride a horse.
Kill ten horse riding guards by air assassinating them.
Perform ten Double Assassinations.
Disarm and kill five guards with their own weapons.
Kill five guards within ten seconds five times.
Have ten streaks of at least five kills.