We present the design and preliminary results of the validation of the Player Experience Inventory (PXI). Based on the input of 64 experts in the field of player-computer interaction, we designed and refined this new scale. Our scale is based on the MDA framework (and on Means-End theory, underlying MDA). The PXI incorporates two subscales, one with dimensions at the functional level (i.e., dynamics) and one at the psycho-social level (i.e., aesthetics). The initial results, via principal factor analysis, suggest the scale can be used accurately to evaluate player experience. This work is our first step towards presenting a new, validated survey instrument for player experience evaluation.