Use the Charge ability 3 times against your target as the Gladiator in a single session of any multiplayer mode.
The Gladiator is the male character with the metal helmet and armor. On the selection screen he is the 5th down in the center column.
This can be earned in ANY game mode; this includes Solo Training Ground (thanks PrinceRules64)
You will need to be at least level 20 before you can earn this achievement, as you wont be able to purchase the "Charge" ability before then. If you're not yet level 20 then I recommend working on the other multiplayer achievements first.
I don't know how familiar you are with the multiplayer modes so I'm just going going to assume you know very little and cover all the important information, feel free to skip any part of this that you don't need.Setting up your abilities
In the Multiplayer main menu you'll want to push LB on your controller then select "Abilities Sets". After that you'll want to buy (with Abstergo Points) or select any of the non-default sets.
Select "Ability 1" or "Ability 2" depending on if you want to assign the "Charge" ability to the LB or RB button respectively. Once you selected which ability you want to assign it to you can buy the Charge ability for 55 Abstergo points.
If you have Abstergo points to spare I recommend adding at very least the faster cool-down perk as this will help you earn this as well as the other DLC achievements faster.
Make sure you select this ability set when entering a multiplayer match, if you forget you'll have the option to change it whenever you die by using the D-Pad and A-button.Setting up the game
This achievement can be earned in any game mode, public or private, however I recommend using the training session as you will have unlimited time and very easy target with no competition. If you want to earn this in a real multiplayer game mode then Deathmatch is probably the most appropriate.Using the Ability
Basically when you push the button to use this ability your character will glow and run straight forward very fast, if they come into contact with your target they will perform a kill with no chance for a stun or a contested kill. You can turn left or right slightly but you have very little control once you activate the ability.
Your best bet is to identify and lock on to your target using the left trigger. Once locked on make sure you're facing them directly before activating the charge. The charge has more range than a normal kill but you're much more likely to land it if you're closer to your opponent. The charge will only count if it connects with your target and results in a successful kill.
Once you use it you will need to wait for the ability to cool-down before you can use it again.Strategy
This is a fairly straight forward achievement. You'll basically want to find and kill your targets as you normally do, except use your charge ability instead of the X button. Obviously for this to be most effective you'll wan to stick to level ground and stay off of objects, stairs or rooftops.
All three charge kills must be made in the same session and there is a substantial cooldown time so try to work quickly.
The achievement should pop the instant you've made your third successful kill with the ability.
I welcome any other tips or strategies for earning this achievement. Thanks for reading!