As it were the Captains and Espada were battling in Karakura town. Kitaro had been sent to secure the castle of Las Noches and so it would seem that an Espada had been left to guard it. If for whatever reason the battle was inconclusive above, in the world of the living, then there would be a struggle for power among the subordinate level of the losing side and, of course, the war could never end. Especially with one large elite level battle. Thus the control of the enemy stronghold with an elite level warrior would be a major play. Even if the victory was assured, control of the enemy stronghold was the next objective and would provide much trouble for an army to come in and have another major battle after the elite warriors took care of one another up in Karakura town.
So upon reaching Las Noches through the portal created by Senkaimon Kitaro stepped out calmly. His zanpaktou resting easily at his side and humming as if peaceful. A quiet moment of solace before the radar-like sensing of reiatsu took place and took up a significant portion of Kitaro's attention to pinpoint the most powerful arrancar pressure within the area. Having found it on top of the dome Kitaro registered his opponent in his mind and cracked his neck. Then dissapeared.
Kitaro soon re-appeared in Zento's face with his zanpaktou unsheathed in a straight cutting move that would rise from the lower left section of Zento's torso to the upper right section and curve near the shoulder not to lodge within the shoulder blade but rather to slice around the shoulder blade bifurcating the enemy's shoulder but mostly cutting the central region of the torso into two, separate yet equal pieces, just like how the blacks and white were during segregation way back in the time of Johnathan Carver during a brief and hilarious visit in the United States involving a bullet.
So, Kitaro sliced as he was re-appearing in front of Zento and by the time he was fully visible with his captains robe flashing behind his back and yet not revealing the symbol of division written on it. Doing so Kitaro had been able to directly speak the double incantation for Hyapporankan and Soren Sokatsui to create a wide area technique that would obliterate and seal the movement of anyone that was in front of him, which left a strong option to come around from behind using the famed Sonido technique. So while the techniques of Kido were blasting with Hado and Bakudo in front of him with full incantation effect Kitaro spun behind him slashing vertically at the first moving thing in his perception of spiritual energy as well as vision before creating a block of reshi and quick-stepping to the standing point of his creation directly next to the dome, to observe his handiwork.