Champion's Master of Metal and multiple sources of impale clarification

Quick clarification please with Master of Metal and multiple sources of impale.

Master of Metal you gain flat phys per impale on the target... this is a global statement to me. So I assume if three players are stacking Imaple on a single target, say for a total of 15 stacks, then the flat phys maximum gained should be (6 to 12)x15 in theory... right?

If anyone can confirm this or correct me that would be great.

Thanks!

well, each player will get 9*x phys damage added, where x is total # of stacks

9 flat damage isnt a lot nowadays though so the more hits your or allies make, the better it is.

Im trying to build a cyclone summoner champ off the concept. aura effectiveness + bunch of phys (or partially phys) summons.

prolly wont have rooms for zombies, but zombie phys slam impales should hit very hard.