“Thrallium” is the name given to the glowing green mineral discovered by Feelix Von Ick and his APEX Laboratory associates in the 1940s. The element is mined from a single large boulder unearthed during an archaeological excavation and kept hidden for decades in the catacombs underneath R.O.P.E. Mansion. The boulder is believed to have crashed to earth millions of years ago, perhaps in the same radioactive meteor shower that gave Valaya (the current Valiant Woman) her fantastic powers.

Over the years, APEX scientists have discovered a number of uses for Thrallium crystals. Radiation from the mineral is known to have an effect on the human mind, and prolonged or intense bursts of radiation can cause anyone nearby to become a compliant – sometimes mindless – slave.

A single Thrallium crystal contains an immense amount of raw energy. APEX technicians have been able to harness that energy to power many of their machines and equipment, most notably the H.E.R.-TV transmitter andraygun, Sentius’s factory, MilkMaid, and Sentius’s android body. Not coincidentally, those objects powered by Thrallium also end up exhibiting some sort of mind control powers as a side effect.