Talk:The Black Cleaver/@comment-24.63.205.91-20130101052347/@comment-218.186.15.10-20130109182138

They did say that there was a reason that it's true damage though:

True damage means that the ability will not be too strong against squishies compared to tanks - if it was physical damage, the actual damage would have to be higher than what is is now to make it balanced; after all, all champions have natural armor gain, meaning that his ult will become really weak for what it does.

Having the damage as true means that they can lower the overall damage, but make it affect both squishes and tanks equally, so that you don't feel like you wasted a ~90s CD nuke doing jack squat, while ensuring that the ability doesn't 1-shot squishies at the same time.