The vortex was never supposed to be damage dealing. It was just a way to temporarily remove part of an enemies army to deal with the rest, and then when those came back you can deal with that. Many players chose to not let their army split up so they would force whatever didn’t make it into the vortex in, effectively just putting the entire fight on pause until the vortex finished.

Then the archons started jumping into the toilet. And hilarity ensued causing a match ending play when the splash damage of the archons would wipe an entire army.