Hypercardioid is similar to supercardioid, except that it offers an even narrower picking pattern. At the same time, it is also more sensitive to the sounds coming from the rear. Sounds from the rear end are being picked from a wider angle and with a greater amplitude than that of a supercardioid. Although a hypercardioid is commonly used in the most aggressive environments, it is important not to point the rear end to any other sources of sounds or noise, and especially speakers. On the other hand, this polar pattern will still perfectly reject the sounds coming from the angles of 110 and 260 degrees.
You can use it to your advantage with the stereo speakers positioned accordingly. When performing on the stage you will notice that speakers aren’t placed in the middle but more on to the sides. For this reason, hypercardioid becomes more advantageous in terms of feedback than a standard cardioid, which cancels only directly from the back. This is especially true for the weaker vocals requiring more amplification. Hypercardioids are also preferred indoors for rooms with little to no sound isolation. This helps rejecting the unwanted sound reflections typically coming from the sides. More information about polar patterns!