Quantum dot lasers have proven to be extremely interesting in terms of nonlinear dynamics. One of the key benefits is their highly damped relaxation oscillations. In this work we take advantage of this stability in a master slave configuration. We find a novel, dual state excitable dynamic resulting in antiphase operation between two lasing states in the device. We interpret the behaviour as a non-Adler but still Type I excitability. Phase measurements bolster our interpretation.