Originally Posted by StayonTarget
There is either a 7th perk or you need to kill the jumper round by only knifing.
Just got down with a few hours of solo. From what I can tell there us 7 perks. I had all six perks and two pack a punched guns and no achievement. Here is a thought I had. When you ar on the roof and run up the dragon ramp turn right and drop down. After that turn left, you will be staring at a 3 building that looks like you can fling over to. I tried but had the fling machine to far right. I had to give up, but I'm 99% sure it can be done. If there is a perk there great, but thus may also be were the easter egg is. I have yet to find a place to build the nav card machine. Will try nore tomorrow after work.