A weapon with BLAST (X) has an area of effect with a radius of inches indicated by X. If this weapon targets a model, this radius is measured from the centre of that model’s base in all directions. If this weapon targets a point on the ground, this radius is measured from that point in all directions, including vertically. If the Attack ACTION with this weapon is successful, it hits every model within this radius that the target (either model or point) has line of sight to (i.e. not completely blocked by terrain).