An extremely damaging spell to any target foolish enough to stand still in it. Multiple Lightning Walls can be stacked on top of each other, increasing the damage proportionally. Most monsters will not advance into the lightning, but this AI can be used against them. Simply cast a Lightning Wall in front of them, and then cast one on top of them. They will stand and sizzle since they're not smart enough to move backwards out of the line of fire. This is a very popular way to kill Diablo himself. The central sprite of the Lightning Wall does double damage, so be sure you target the monster you are usingit on.

Like Firewall, Lightning Walls work best when cast in a straight line, rather than diagonadiagonal, since there are gaps between the active sprites on diagonal walls. Lightning Wall deals double the damage of a Firewall, but it seems to have more gaps and spaces, since monsters are more likely to walk right through it.