Talk:Oblivion Orb/@comment-9866292-20181015022144/@comment-26808509-20190802110416

You are right, it's simply because there is no basic magic pen item. Flat magic pen, just like armor pen, is a really early game focused stat. With Oblivion Orb and Sorc shoes you gain 33 magic pen, which will cause you to deal true damage- or close o true damage - to everyone who doesn't buy early MR and that gives a bigger boost in damage than higher AP values with the same price would do. In other words, it's a pretty cheap powerspike for mages and AP assassins.

However, flat magic pen falls off pretty hard. The MR per level alone is enough to exceed the 33 MR, addtionally everyone is easily able to buy MR without sacreficing too much for it (which wasn't allways the case). Usually, if an enemy has 40 MR or more, Void Staff becomes better damagewise than Morello.

That being said, it's kind of logical that there is only one flat pen Item (Morello), because the stat falls off hard. Having multiple items with that stat would either lead to multiple items that fall off in the late game or they would have to make the flat pen stack. And the latter case would be really unbalanced, because ADC's or other mages would no longer be able to itemize against it. Mages and AP assassins would deal true damage over the duration of the whole game, because they would naturally stack all these pen items.

Morello functions so well because, although the flat pen falls off, it still has a situational use in the late game with the Grievous Wounds. Finding similar things for addtional flat pen items would be really hard, if not completely impossible.

But back to Oblivion Orb. I think this item is good as it is. It is a cheap early powerspike, as it gives you a nice damage boost against low MR targets in the early game without needing to complete a full item. If there are healing champs in the enemy team it can be upgraded. If not, however, it can be sold in the late game for a stronger item (as you should allready have Voidstaff around this time). And since it has a decent resell value, you don't even lose a lot of gold doing so.