There inst an exact way to make it stable. It all depends on the stuff such as supremacy, mount procs, skill procs, aegis skill, Void mail/Pandora mail etc.
Let me give you an example. In the first scenario I cast my tree skills and hence I get all the buffs from my mounts considering all my mounts have 100% hit proc rate, which can increase my overall attack as well as my heroes\' attack. But in the second scenario I only managed to cast one skill and hence getting only one buff. That means my attack won\'t be as high as if I would have of gotten all 3 buffs
Does it make sense?
There are quite a lot of reasons involved but I only listed a few, otherwise I would be here all day