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The brightest central galaxies (BCGs) are the largest and the most massive galaxies in the universe. Their origin is still under debate but major mergers should play a key role. While there have been several dramatic examples of local BCGs forming via dry mergers comma BCGs are believed to mainly form with wet major mergers at high z and there has not been a local analog of such systems. We have searched for BCGs forming via wet major mergers in the local universe and have found a spectacular example of a trio of star forming galaxies with comparable luminosities and within 15 kpc from each other. We propose joint Chandra-HST observations to study AGN comma ULXs comma diffuse X-ray emission and mergers in this rare system. The results will shed light on the important early stage of BCG formation.