- Abstract Violent cluster mergers provide a unique opportunity to study the interplay between dark matter (DM) and ICM and to set constrains on the nature of DM. In particular, cluster mergers near first core passage allow us to see DM by comparing the spatial distribution of the intracluster gas (baryonic) and DM. We have recently finished a lensing analysis of a strongly merging cluster, A2744, the" Pandora cluster". We found that it is the result of a multiple cluster merging, more complex than the" Bullet" cluster, that produced a wide variety of new phenomenologies, among them a Bullet, a Dark sub-cluster (no gas), a Ghost substructure (no DM), which can provide fundamental insights to the physics of the ICM. Here I will present the current results of the X-ray lensing analysis of this spectacular cluster.