When I saw the iso-8 sale was at 900% bonus I was kind of hoping that they would do the same for the HP sale. 
Ok, I really wasn’t expecting it to be that high. 
Honestly, I’d like to meet the person who buys ISO.
I did bought ISO twice. In 3 years. Simply with 3* championing costing 120k, 4* 380k and 5* 450k that 900% numbers should be standard not bonus. Imagnine you didden stash which would be normally 132 000 but you got 13 200 000. Probably wouldnt be 900% but 200%. I think.
If you are playing on Steam, you can get the Nick Fury Doomsday plan, a one time offer. 30.000 HP for (now) €84,99, but I got it at €9,29 in an end of year sale.