The mechanic
The Cinderbrood Matriarch is a slow, wingless brood dragon with a large health pool and no armor of her own. Left alone she simply marches, but hurting her is what starts the trouble.
Every time she loses 15 percent of her maximum health she drops a stationary armored egg behind her, up to 6 eggs across her life. Each egg sits on the path and does nothing on its own, but it is armored and immune to crowd control, so it takes focused fire to crack.
An egg that is not destroyed within 8 seconds hatches into 3 quick cinder wyrmlings that sprint for your base. Ignore the eggs and you face a steady stream of hatchlings on top of the matriarch herself.
How teams beat it
Peel damage off the matriarch to smash each egg inside its 8-second timer, since a cracked egg is far cheaper than three wyrmlings. Armor pierce speeds up the egg kills. If you can burst her down fast you skip the later eggs entirely.
Like every boss, it fights inside the showdown rules: kill it and it respawns about twenty percent stronger on the rival's lane, let it leak and it crosses unescalated. The full showdown rules are in How a match works.
