What ohm load will 4 12 in dual 2 ohm play at?

There are a lot of possibilities here, especially since your question is Worded exactly right.

I'm taking it you have 4 12" speakers, each of which have Dual Voice Coils (2 Ohms each). You want to wire them together and see what ohm load you have.

Ok, there's multiple ways to wire this up. Series, Parallel, and Series/Parallel combo.

Wiring these speakers in series can give you either a 4 ohm load, or a 16 ohm load. 4 ohms if each speaker by itself (having DVC) is wired in parallel and 16 ohms if each speaker by itself is wired in series.

Wiring these speakers in parallel can give you either a .25 ohm load, or a 1 ohm load. Again .25 ohms if each speaker by itself (having DVC) is wired in parallel and 1 ohms if each speaker by itself is wired in series.

Wiring these in a series/parallel configuration can give you tons of different wiring options and ohm loads. In your case .75, 1, 3.2, 4 ohm loads.

So your best option would to be wire your speakers up in series, with each speaker wired in parallel to itself. This way you'll get a 4 ohm load, if done properly. Make sure your amp can run a 4 ohm load too.