Anivia's crystallize (w for wall)

A wall supposed to be impassable, which block all mouvement as the description of the ability say. Yet, most of the champ can just jump over it or dash through it. It would be great if it could have an effect like Poppy barrier that stop dashes, or be like Cassiopeia's miasma and Singed's Mega adhesive that deny the use of mouvement ability. If some argue that it would be too ''broken'' or ''over powered'' adding a slow area really close to the wall that trigger the e double damage so hero that dash threw or walk on the wall would be slowed and could be threaten to recieve some big damage.