Rumbledrugs became notorious for their use during the Insurrection, most notably on Hellas and Fumirole. On both worlds they were used by rebels in a vainglorious attempt to fight Spartan-II's. Unencumbered by the body's normal safety limits, subjects were capable of feats of enormous strength; however, the subsequent lack of control and mental instability together with the immediate physiological damage meant that users often died long before they ever laid hands on an actual Spartan, but not before doing tremendous damage to themselves and anything that got in their way.