We have developed a new version of the HOMME dynamical core that solves the Deep-atmosphere equations, which removes the Shallow-atmosphere and Traditional approximations. This modification restores the so-called Non-traditional Coriolis Terms (NCTs) to the dynamical core, which is predicted to impact atmospheric dynamics at the equator significantly. We present an overview of the modified HOMME dynamical core. We present results from a spectrum of dry idealized test cases that validate the correctness of the prototype and elucidate the dynamics of the deep atmosphere. We have developed a new version of the HOMME dynamical core that solves the Deep-atmosphere equations, which removes the Shallow-atmosphere and Traditional approximations. This modification restores the so-called Non-traditional Coriolis Terms (NCTs) to the dynamical core, which is predicted to significantly impact atmospheric dynamics at the equator. We present an overview of the modified HOMME dynamical core. We present results from a spectrum of dry idealized test cases that validate the correctness of the prototype and elucidate the dynamics of the deep atmosphere.