Not that anyone was asking, but I'm just looking at the emblem guide and trying to work out the most efficient way of unlocking everything in the game (necessary for the platinum trophy). I think you can do it in 8 playthroughs, which breaks down like this:
Playthrough 1. Do a Chicken emblem run. This, if you plan properly, can encompass the following emblems:
Bear - 100 CQC choke kills
Eagle - 150 headshots
Blue Bird - Give 50+ items to rebels
Hawk - Be praised by allies 25+ times
Ant - Do 50 body searches
Gibbon - Do 50 hold ups
Tortoise - Spend 1 hour in a box or drum
Rabbit - 100 playboy page turns
Bee - Inject 50 PMC soldiers (must wait until after the Act 2 boss for this to get syringes)
Gekko - 1 hour of wall hug time
Scarab - 100 forward rolls
Frog - 200 side jumps
Inch Worm - 1 hour crawling
Lobster - 2h30m crouching
Hyena - Pick up 400 weapons/items
Hog - 10 combat highs
Pig - Use 40 healing items
Cow - Over 100 alerts
Crocodile - Over 400 kills
Giant Panda - Over 30 hours played
Puma - Over 75 alerts, over 250 kills, over 25 continues
Chicken - Over 150 alerts, over 500 kills, over 50 continues, over 35 hours played, over 50 healing items.
I suggest doing this first to unlock the corpse camo because it's very useful for 0 alert runs.
Playthrough 2 to 7.
Get one of the following per playthrough:
Tarantula - Under 75 alerts, over 250 kills, under 25 continues
Centipede - Under 75 alerts, under 250 kills, over 25 continues
Spider - Under 75 alerts, over 250 kills, over 25 continues
Jaguar - Over 75 alerts, under 250 kills, under 25 continues
Panther - Over 75 alerts, over 250 kills, under 25 continues
Leopard - Over 75 alerts, under 250 kills, over 25 continues
During one of the first three of these also get the Assassin emblem (kill or stun 50+ enemies with the knife, 50 CQC holds, less than 25 alerts. Easy way to do it is slit the throats of 50 enemies while in a CQC hold).
Playthrough 8, the big one...
Get the Big Boss Emblem. If you've done the prior 7 playthroughs as described, you'll get:
Big Boss - Play on The Boss Extreme, finish in under 5 hours, 0 alerts, kills, continues or healing items.
Fox Hound - Play on Big Boss Hard, finish in under 5h30m, no more than 3 alerts, everything else zero as above
Fox - Solid Normal, under 6 hours, no more than 5 alerts, everything else zero as above
Hound - Naked Normal, under 6h30, no more than 3 alerts, everything else zero as above
Mantis - 0 alerts, continues or healing items in under 5 hours
Wolf - 0 continues or healing items
Raven - Under 5 hours
Pigeon - 0 kills
Little Grey - All 69 weapon types
Scorpion - Under 75 alerts, under 250 kills, under 25 continues.
All in one go. It won't be easy but it's the quickest way to get them all. It's best to have as much stuff as possible before trying the BBE, even though you can't even carry that much.
I really hate the Scorpion - Puma emblems, they're just tedious.
Oh and the mandatory Gekko spotting, is that in the marketplace in Act 2?