I’ve beaten all of the 3 star Challenges, and in my opinion the hardest one was the 2-star “Be More Objective” Challenge.
For the “Be More Objective” challenges, I’d recommend starting a new character and just attempting it from Level 0.
In my experience, the key to Be More Objective is using an Assault Rifle with the Grenade Launcher attachment to knock down enemy players at key times so that you can finish off specific enemies (i.e. the engineer and the medic).
When it comes to completing the Soldier component, you can just sprint to the objective and plant the charge without being disrupted. From there, just grenade the engineer and gank him to ensure that the door blows.
For the Engineer objective, I find that picking a favourable route to accomplish some slaying before doing a suicide Engineer Repair is the best way to slowly work towards completion. I find your bot teammates particularly deficient in helping you establish a position in this component of the “Be More Objective” Challenge.
The worst offender in the 2-star Be More Objective Challenge is the required Operative hack. To accomplish this task, you will need to work your way towards the Objective by slaying sufficient numbers of the enemy team single-handedly. Once you have pushed them back a bit, rush to plant the hack box and quickly take cover. You can count on the enemy Engineer attempting to dismantle your hack. You can also count on your AI allies not being very helpful outside of the occasional distraction. Thus, you will need to have your grenade launcher ready to quickly kill the engineer then rush to re-setup your incomplete hack and run for cover.
The final dash to the drop off point is pretty straight forward, and you’ll need to kill a couple enemies who will beat you to it. I recommend the grenade launcher opening following by killing them when they are weak before you complete the drop.
If you need to see an example of this being executed, then I recommend a video that Machinima has up on Youtube for the Be More Objective Challenges (Seananners is playing).
For the 3 Star “Tower Defense” Objective, there is a great Youtube guide which, again, places a heavy emphasis on the grenade launcher AR attachment to take out clumps of enemies and, in this case, prevent enemies from taking the Command Post. I think you can complete this Challenge at nearly any Experience Level, but I’d recommend getting the Engineer weapon buff, Level 3 turret, and Extra Land mines.
The “Escort” Challenge is, for me, just an instance of slaying the enemy as effectively as you can to keep the bot moving. I tend to run out of ammo before I die in most cases. The real difficulty of this Challenge is getting the bot up and running while keeping tabs on the enemy players in the mean time. I recommend a Grenade Launcher attachment primary Assault Rifle with any SMG secondary. The only time I use the Engineer skills is when I plant a mine by the first door before repairing the bot (I also buff my gun’s damage). I tend to avoid capturing the Enemy Health Command Post on the 3 Star version, because I find my time is better spent just pushing the bot forward. The only times I capture the Command Post on the 3 Star Challenge are when I’ve killed all the enemies and I’m nearly out of ammo as I approach the last corner. In this case, I can multi-task escorting the bot while also getting a timely resupply of my ammo. Otherwise, I don’t bother.
The route for completing the “Parkour This” Challenge is pretty clearly illustrated in this youtube video. You don’t even need to follow it, but I found it interesting to see how someone really skilled can push the limits of Brink’s Parkour mechanics.
