[DeAtHaBiT]

Originally Posted by fireman_socom

I dont remember that mission on Campaign mode too well, but in Instant Action, have one person grab an M4A1/M16A2 (I perfer the M16) with M203 Smoke and the extra M203 Smoke.

There are 5 places you need to use the 6 smokes you have (going up the middle, in order):

1. At the end of the first statue
2. At the middle concrete circle
3. At the concrete thing with the walls entrance
4. At the other end of the concrete thing with walls
5. And lastly, at the half wall thats right before the building

If you shoot M203 Smokes at all of these places, you will make it in the building every time unseen (JUST IGNORE ANY MERCS; DONT SHOOT AT THEM!)

I beat the whole game, Campaign and Instant Action on Admiral (that means i completed Snake pit in all 7 missions), and unlocked the R44M and the MM-1, so this^ comes from experience

PS - Oh yeah, now I'm thinking back to the Campaign mode, and I think I remember it now. Im pretty sure you dont have to kill any Mercs until you got into the building, and there was even a Secondary Objective where you had to make it to the building unspotted. If this is the case, then using the tactics above should work for you.

Exactly what me and Muk did.