Ok first of all from what i can tell, their is almost no correlation to your ranking and your performance, despite all the speculation people have been saying and believing to be true.
Someone thought the slashes were a level-progress counter whereby you change rank after reaching 5 slashes, which cannot be right. Since you only EVER see a [Skull+Knife] and [Skull+2 Shotguns] rank with 4 or 5 slashes. The FIFTH slash seems to be directly related to the Blue Eyes effect.... 5 slashes means blue eyes, 4 slashes means no blues eyes (i'm sure alot of people have noticed this)
I was stuck on 4 slashes [Skull] for days and days. ALL my friends had the Blue Eyes effect; i was the only person who didn't... even though i played zombies;
Had More Kills, Headshots, Revives, (less)deaths
Higher on the Leaderboards
Sometimes never died in a game
ALL MY STATS WERE SUPERIOR IN EVERY WAY
This is how i knew the stats had nothing to do with the 'B-E' effect.
Some people have been saying, "yeh, if you get 600+ kills with little downs" and "If you beat your previous best round" I just finished a 600+ kills with only dying as the finish and also got to wave 22 with 160k points... and guess what? nothing happened. I've also done a 200+ melee SPREE to see if i could get the [Skull+Knife] rank but that also did nothing.
ANYWAY i had a breakthrough with the 'B-E' effect... I thought it must be something you do, specifically, IN the game...Something that all my friends have done/do regularly??? Then i remembered reading about people who have been losing there Blue Eyes/being De-ranked or Demoted. (I have now lost the blue eyes because i haven't been able to play for 2 days, so i'm pretty sure you get demoted for not playing regularly and/or doing really bad but i'm just guessing) Anyway, it was this idea of people being de-ranked which made me think the blue-eyes was a temporary thing like you had to be 'CHARGED' and overtime you lose your 'CHARGE' which makes sense as the other ranks can also be 'CHARGED'. Possibly even related to the Easter Egg, I watched a video from NGT where 'spiderbite' thought it could be 'zombie vision'...
So i woke up one day, realising this 'CHARGED' concept, and thought... well how do you get charged? It's got to have something to do with the POWER or ELECTRIC TRAP right? also realising i've never used the electric trap properly but my friends use it all the time. AND i've seen my friends sit in the POWER room when you turn on the power, constantly getting stunned by the lightning, which i never do because i've always thought it was a pretty stupid/pointless thing to do.... AND EVEN seen atleast a few of them accidently down themselves with the electric trap.
SO.... i start a SOLO game, get straight on the bus using the turbine, go to the power room in round 1 making sure to keep a zombie alive, turn the power on and sit in the power getting hit by the beams, then i built the electric trap, killed the last zombie with it. Then just to make sure, i ran into the trap to eletricute myself and end the game at the end of round 1.
AND GUESS WHAT HAPPENED...
after playing 20 stupid games the previous night with no success, THIS ONE 5-MINUTE GAME GOT ME BLUE EYES!
Now i thought i had solved it, and was getting ready for some 'BLUE EYES SOLVED B***CHES' thread. But like any smart person, i thought i'd double check my findings/make a proof video/narrow down what ACTUALLY caused me to rank-up etc.
However i immediately jumped on my brothers account, who was the exact same rank as me [Skull], and started to narrow down the results;
A) just sitting in the power room then commiting suicide.
B) just killing one zombie with the electric trap then commiting suicide without downing myself with the trap.
C) only downing myself with the trap and no zombies.
None of these worked and he didn't unlock 'B-E'. I tried doing all of them again, exactly like I did. (i've saved the video) and that also didnt work. Unless theres something else that you must do individually before you can even be considered to be 'CHARGED' but that could be anything. Especially when none of my friends have completed either of the Easter Egg storylines, except build the obelisk. Or doing anything except build stuff, buy perks and kill zombies, and they've all got blue-eyes (also my brother's done everything i have, story related)
Like i said, i've been de-ranked back to 4 slashes [Skull] since all this, and i've tried doing what i've said above but it hasn't worked. BUT IT CAN'T JUST BE A COINCIDENCE, after i played all those games, trying different things, trying to rank-up... then i just aim to do this specific thing one day and BOOM i get it. (and with the worst performanced game ever)
I've literally exhausted everything i can think of for now, and think i should pass this over to the community. Also how do i upload the video from my theatre?