I usually don't like lying but i guess this opener is something i could do, and it seems good to use on the subway and other stuff like that,
Go up to some HB with a curious face, or a suspicious face xD and say:

Pua:Hey, aren't you ("some friend of mine") friend? i think we met at party X (try to callibrate the party with the chick, and don't lie about going to that party)
HB:Hm, No i don't think so... (worst case scenario)
Pua:What?! you have no ideia, i was so convinced it was you xD maybe you have a twin sister!! I know she went to X college, but i really don't remember her name, (Transition)

Never used this, but whenever i open with something like this it works great, i have a really big problem with opening in the subway in the morning, and i usually see hot chicks there, but because of having everyone looking at the PU i usually don't even open there.

Hay Conguy
Are you in NYC?? I'm in BK.

I soooooo want to open sets in the subway. I see a lot of HB's down there.
However,..if your on the platform,..you don't know when the next train is coming.
If it comes to soon, you open was waste of time.

If your in the car, you don't know her stop.
Then,..a fucking mariachi band comes in and fucks up the open.

Tell me,..do you have a strategy for this??

I never opened in the subway in the morning, just when i go out, if she leaves i can go out of the car, and ask her number or ask before she left. it's better to think of that in the moment

In subway? Offer her a footlong and make sure you can deliver.

In subway? Offer her a footlong and make sure you can deliver.