For Ishtar, the effects weren't immediate.
One heartbeat ticked by, and the glowing-horn Oni watched as her counterpart dodged the blast that had been levied against her in a swirling hoary mist; and for a moment the Oni wondered if she had been building this all up in her head far more than she should have ... Then another heartbeat happened, and another, further cementing Ishtar's concern. So it came as some great surprise when, without warning, pain came flooding in.
"Ah ..."
Clutching at her chest with ragged breaths forced through clenched teeth, she found at least -- despite the pain -- some solace in the familiarity. In the end the pain did not last long however, and without warning it receded back from where it had spilled forth. Before Ishtar could express any kind of concern however, she felt it. A slow, almost melodic pulse of something she'd only ever felt a trickle of before ... and she understood what it meant as much, or more, as she understood how and why civilizations rose and fell:
The inevitable had come at last ... and with it, a night to remember.
And as the energy she'd once found herself all but deathly afraid of welled up from a now unblocked source to permeate the very fiber of her being; Ishtar looked up at her counterpart and flashed a humorless smile as her own Hakai enveloped her.
Now, fully transformed -- as she had been on a night five thousand one-hundred and twenty two years ago -- the golden-eyed Oni took a moment then to glance down at her transformation, taking stock of the changes and their similarities to the state she'd seen, previous; and for the first time in a great while three words were offered at the sight of herself. "How passing strange ..." In the end however, it mattered little. The time for care and concern for her own well-being had come and gone the moment she'd stepped through the RoSaT Time Gate; and with it any notion of surviving this counter -- if she managed such at all -- unchanged. So she looked up once more, and finally acknowledged herself.
"Playing for keeps ?" Ishtar replied, almost mockingly as she took a step towards her doppelgänger, the icy floor beneath her buckling under an unseen strain. "No ... we are
well past keeps." With an almost effortless motion then the where once Ishtar had been standing exploded outward in a spray of rapidly disintegrating ice shards as the now transformed Oni launched herself at the Goddess of Ruination; appearing before her opposite in a flash before Hakai-tipped claws sliced through the air and towards the Oni-Alter's throat.