Galio's new ult gives me an idea

So I don't anticipate this to be added to Galio's ultimate, but I think it would be interesting if his ultimate, or an other/a new champion would have an ability that causes enemies to deal reduced damage to allied AND neutral monsters. .. possibly and/or structures.

This could be used to make it difficult for enemies to accurately judge damage needed to secure major objectives like Dragon and Baron, or to finish off structures such as towers, inhibitors, and the Nexus.

Again, I don't see this being something that would be done with Galio, but the long range AOE effect made me think that it would could work to potentially disrupt the enemy's attempt to take these objectives instead of only buffing allies with damage reduction.

So just an idea.

Take it or leave it.