How come Sontarans are massive chocolate addicts in Doctor Who: Flux? The Sontarans debuted in 1973's medieval-flavored Third Doctor adventure "The Time Warrior," popping up regularly ever since to take another crack at invading Earth. Despite being obsessed with warfare and combat, the Sontarans have always ranked among Doctor Who's more comedic recurring villains thanks to their infamously potato-like appearance. That was until Doctor Who: Flux's "War of the Sontarans," which presented the baddies at their most ruthless best... but that old comedic streak couldn't stay absent for long.
In Doctor Who: Flux's finale, "The Vanquishers," the Sontarans occupy Earth for a second time this season (a new Sontar record, surely?) and hatch a plan to conquer the universe by exploiting the Flux. Jodie Whittaker's Thirteenth Doctor needs to infiltrate Sontaran command, and UNIT's Kate Stewart reveals an unexpected new weakness in the Sontarans' armor - and we don't mean their probic vent holes. This new wave of Sontaran invaders are ransacking England's many corner shops, shoveling down chocolate, candy, and fizzy drinks galore. The promise of more sugary snacks even convinces one Sontaran to accept The Doctor's terms, ultimately leading to their demise.
So, why do Doctor Who: Flux's Sontarans now come with a devastating chocolate downfall? There's nothing in Doctor Who's past canon to explain this (admittedly hilarious) new trait, nor any historic sugar binges during the Sontarans' previous episodes. In typically rapid, jargon-filled fashion, The Doctor attributes the Sontarans reliance on chocolate to "metabolic processing." Something about Earth's reduced gravity and gas composition has, according to The Doctor, given the Sontarans a liking for Earth's sweet treats. More than just tasting good, Shallo the Sontaran appears slightly tipsy off the cocoa high, slurring his words and hiccuping - perhaps explaining Whittaker's scientific ramble about restorative gas and metabolic processing.
Doctor Who: Flux's "War of the Sontarans" episode might account for why the extra-terrestrial root vegetables haven't gorged on Earth candies until now. When the Thirteenth Doctor and Mary Seacole kicked the Sontarans out of Crimea several episodes ago, they did so by cutting off their supply of energy and gases during a 7.5 minute window of probic vent refueling. To avoid the same fate, maybe this second wave of Sontarans in "The Vanquishers" opted to refuel the traditional way, munching on Earth sugar instead of injecting their own pure energy. Allowed a rare test of proper food, it's hardly surprising the Sontarans developed a fatal preference for chocolate, candy and soda.
Though the science behind Sontar's collective sweet tooth is... ambiguous, the behind-the-scenes reason for their chocolate addiction is obvious - comedy value. After the Jon Pertwee and Tom Baker eras, Doctor Who's portrayal of Sontarans become increasingly comedic, culminating in Strax of the Paternoster Gang. Though "War of the Sontarans" highlighted the brutal, warmongering side of Doctor Who's Sontarans, "The Vanquishers" errs toward the opposite end of the spectrum, accentuating the humor. And what could be funnier than a deadpan-serious race of warriors, bred for the battlefield, being brought down by Cadbury's finest.