scarlet forge
It lowers the capabilities of most heroes with an animation that interrupts their basic attack with a slow battle skill specially if they actually rely on basic attacks, instead, make it as fast as basic atks and scale with it.
In addition to this, make their ultimate animation finish IN the time stop/pause like said in the title, as you can see it is still in animation after the time stop/pause consuming 1-1.5 seconds which could have done 1-3 basic attacks during that time as the example shows.