Order Only: Private message to Hydra Lestrange, Mr Snape, Sirius Black, and Auror Brodie

I've been thinking about the spell Bellatrix Lestrange used to kill Dorcas Meadows. It's what Benjy Fenwick died of as well, wasn't it? And Sirius almost did.

Auror Brodie, do you know how to cast that spell? Or are there other Aurors who do?