Buddha's Warrior Attendant Pounds Mortar (金刚捣碓, Jin gang dao zhui), is a posture found mostly in the Chen Family forms of t'ai chi ch'uan. Typically performed from a High Ma Bu stance, flowing with hand movements until reaching a Gong Pu stance.
Buddha's Warrior Attendant Pounds Mortar is a complex movement learn initially for beginners in the Chen Style Tai chi due that this one syntetizes most techniques common in said style.
It's basically a tai chi move wich commence with the left leg moved o the front in a mapu-stylish position (Horse Stance), while both palms join at face height, with a circular flowing motion both arms come to the front (right fully extended with palm facing upwards, while left hover on top of right's forearm, pal facing downwards) while the right leg moves to the front on a Xu Bu stance.
This movement employs first a Lü (Roll Back)-Chin Pu (Frontal step)/Chung Ting (Central Stance) pattern, followed by a Lock with arms and another Chin Pu (Frontal step) putting attention to the hips movement. This stance is completed in Mapu with the right fist on the open left palm in from of the belly. The fist and right foot then raise simultaneously and drop with a stomp and hit to the left hand. On a Practical level this can be used to performed also a K'ao (Shoulder Strike).
Jin Gang, while translated as Buddhas warrior attendant is a term meaning indestructible, it is used for Diamond in the Diamond Sutra. Diamand in Sanskrit is Vajra, for this reason the translation of the move is also given as Vajra pestle.
The vajra is not a Chinese weapon, but is a weapon that was employed in China. It is a sacred weapon to Hindu religions, such as Buddhism. Those familiar with the weapon will note that the move "Jin Gang Dao Dui" is conducive to the use of this sacred weapon.