Z-radiation
From Tardis Wiki, the free Doctor Who reference
Z-radiation was a harmless radiation which was harnessed in the Z-battery, which was left behind by the Third Doctor in UNIT HQ after failing to jump start his TARDIS with it during his exile. The Decayed Master plotted to combine it with O-radiation on Oseidon to create ZO-radiation only to be thwarted by the Fourth Doctor. (AUDIO: The Oseidon Adventure)
