The Infinity's End System is a traumagenic system of four:
• Umbral is the host and core. Umbral fronts almost all of the time and the others are co-conscious.
• Penumbra, Heat Death of the Universe
• Mallory
• Three of Swords
They became plural in 2011 from a peiragenic event. Each headmate thereafter arrived as a result of another such event.
They were one of the founders of Pluralpedia and accidentally ended up being Plurpy's mom.