Revolved crescent lunge (parivritta anjaneyasana) is a great twist to release toxins and tension. It's also one that can be a bit intimidating and make you feel like you are doing it wrong. It's not the most comfortable pose to hold, but that's why we practice yoga—to learn how to manage the uncomfortable sensations on our mats and be even better at managing the uncomfortable situations off of our mats.
There are a lot of things to keep in mind so that you don't get out of alignment and hurt yourself, so I'm going to break down this posture and what every part of your body should be doing while you are in it.