An opponent preoccupied defending the crucifix “double attack” of rear naked chokes and armlocks can be thrown a curve ball when you drop into this guillotine. This choke gets dubbed the Marcelo guillotine because I learned it from Marcelo Garcia at a seminar he gave on the crucifix and because he is so well known for this style of guillotine finish.
The beauty of the Marcelo guillotine is that you don’t need a deep grip around the neck or to close guard like the traditional guillotine requires. Instead, you just need to block your opponent from jumping over to the safe side, and you finish by twisting into them rather than extending away. As a bonus, your opponent’s arm is still stuck between your legs, blocking that arm from helping to defend against the choke.