I recently recorded a bunch of battle cries for a production of "Richard III" with an Audio-Technica BP4025 into a Sound Devices 722 at 24/96k (in case of pitch shifting). I was in the theater space where the play was being put up, which was a large black-box space that was a little live but not horrible. I set the mic up about 10 feet in front of the 15 actors, who were standing in the center of the room. I recorded passes of constant screams, but also short yells, which when put together made for a more dynamic sound than just the constant scream by itself.
Prior to that, I'd been using a big group scream I built in 1998 out of several takes of 5 guys around a stereo pair of 414s (through a Mackie board to DAT) in a moderately dead tracking room at a music studio. I must have used the "Big Skreem" build on a couple of dozen projects since then.