Pantheon's E tooltip is wrong or the mechanic is bugged.

Pantheon's E states (in client): "Pantheon sets his shield, becoming invulnerable to damage from the FRONT and striking repeatedly with his spear."

Currently in game the mechanic is: Pantheon gains invulnerability to damage from any direction as long as hes facing said champion. That means no boomerang abilities, dots that are already applied (ignite included), and non-projectiles such as karthus ult that comes from above. All of this damage is blocked as long as hes facing the champion that would be dealing the damage.

So either the mechanic is bugged or the tooltip is wrong. I for one would really appreciate it if the mechanic was wrong and he wasnt able to just effectively get a free hourglass every 20s. But, I would also be fine if the tooltip/client description was modified to reflect what is happening in game. I don't like being killed by what semantically/technically is a bug, but is in fact design choice. I would prefer to be killed by what is in fact known to me as the "as intended" design.

"Pantheon sets his shield, becoming invulnerable to damage from enemy units he is facing and striking repeatedly with his spear."