- This is only obtainable with a tier 5 or higher tank! Do not buy or complete a contract for tiers 3 & 4 if you are going for this achievement.
For this achievement you only need to earn ONE mark of excellence, not all three.
The general mechanic for this is that you must have an average damage+assist points higher than 65% of the player base who play a specific tank in that specific tank. (For 2 marks its 85% and 3 is 95%)
To earn this achievement, you must earn one of those marks of excellence in a Mercenary tech tree tank or mercenary premium tank. (Credit to WithTheDawn)
Mercenary tanks can only be bought with real money or earned through long missions. After you have the tank, you have to focus on doing well in that tank. Things that can improve your performance is well trained crews, premium consumables, equipment, and knowledge of the game in general.
I'm currently grinding out the contract for the Tusk, so I can't put up any more guides until that's done. But if anybody wants to write one, I'll put it up in the solutions and give you credit for it. I have a feeling the lack of guides is why this solution has so many negative vote.
Guide to the Bulwark
Guide to the Stubbs (Credit to IM TOM JW)
Guide to the Smoothman
Guide to the Absolution (Credit to WithTheDawn)
Guide for the Tusk
(Credit to Rub My Barrel for proofreading and wrong % correction)