Hmmn. In my case specifically, the player would have had to made enemies of the Three Great Kobold Clans (Breezewalker, Steamspeaker, and Flamedancer), likely by doing harm to the gemstone horned creatures, and have made their way to the Temple of Greatmother Tiamat located in Mount Myrrine, home of the Breezewalker Clan.
Having made enemies with the factions of Toralican Kobolds, I would have evacuated the caverns and tunnels leading to the temple as soon as I smelled the danger; there is no massacre awaiting my people.
The candles lining the temple walls are lit, casting a gentle twilight glow with a faint purple hue across the myriad cushions, stones, and benches lining the main hall, facing the altar. A thick haze of rich magenta incense fills the room with the scent of petrichor, tinged with something that leaves the faintest hint of a metallic tang on the tongue.
I await, before the altar, dressed in a deep, dusky purple robe that falls from my shoulders to my ankles. I ask the player why they made enemies of my people. Why did they have to bring harm to creatures who wanted nothing more than to be left alone?
Regardless of the answer, a short prayer in High Draconic follows, and a deep, dark, iridescent ichor begins to seep from my scales as I unleash my twilight flame. Reality begins to sunder around the edges, shards of temple floor cracking and splitting apart, and before long, there's nothing but void, illuminated by distant motes of starlight, and my roaring twilight flame, which has by this point burnt my robes away, revealing a suit of dragonscale mail clad in all the colors of the rainbow, rippling in time with the emanation of my flame.
I'll allow a moment for weapons to be readied, before pulling my flail to my hand, letting the great amethyst-studded sphere of what looks like sapphire come to rest in my palm effortlessly. Instead of metal chains, the ball is connected to the haft by chains of twilight fire, the very fabric of my own soul.
There's no mercy to be had for those who have willfully brought harm upon my people, after all.