We're to believe that the entire Lupari race came to shield the Earth, but wouldn't that include newborns who couldn't operate ships?
Perhaps the Lupari are a clone race, like Sontarans, so they don't have a helpless "newborn"/"young" stage.
Or perhaps they did bring their young along with them; nursing mothers could have a nest box on their ships with the puppies snuggled safely until they need care.
There's a ship for each of seven billion humans. That figure includes the human kids and babies.
Except the human population of Earth as of 2021 was more like 7.8 billion. Assuming the Doctor and Karvanista were being exact about the number of Lupari ships, and that the Lupari have helpless young, there could really be 7.8 billion Lupari individuals, of whom 800 million are young who can't operate ships. Thus, it is plausible that some of the ships have young Lupari on board along with their adult carers (who are the pilots).
With all their capabilities, why would the Daleks, Cybermen and Sontarans not be able to create matter-generating shields themselves like the Lupari? The Daleks in particular pride themselves on their inventiveness.
Most Dalek technology is designed for combat and extermination. The idea of building something to PROTECT is probably too outside the box for the Daleks to contemplate.
Even if this Flux has been extinguished, why have the Ravagers failed Time? Couldn't they just have gone back to Division and generated another one?
They may not know how. Tecteun created the Flux and the Ravagers killed her thinking they'd already won.
Can't the Doctor remove the kill switch from Karvanista's brain? Or at least take two seconds to scan it and say, "There's absolutely no way I can remove the kill switch from your brain without activating it."?
Perhaps using any means of examining the poison injector, like the sonic screwdriver is enough to trigger it; a fail-safe might be hidden in it.
The Doctor wouldn't know that without doing said examination. And if Karvanista knew that were the case, it should be stated onscreen.
But what constitutes "talking"? Couldn't the Doctor just deduct and ask Karvanista to nod/shake to confirm yes/no? She never even considers this loophole?
The TARDIS team successfully bargain with a Sontaran commander by offering the recipe for chocolate, but the Sontarans could easily download that from the human Internet. Possibly Fridge Brilliance, though, as the Sontarans might assume that something as important as that would be a well-kept secret and not freely available.
Why didn't the Sontarans invite the Rutans to join their truce and get rid of all three of their biggest rivals?
Two possible reasons. First, everyone knows how much the Sontarans hate the Rutans so if they'd suddenly extended the three-fingered hand of friendship someone would definitely have smelled a rat and realised that the Sontarans were planning some sort of betrayal. Second, where's the fun in letting some apocalypic force of destruction destroy your hated enemies when you can crush them in battle for the glory of the Sontaran Empire.
It's probably the latter, Sontarans live for war, if they wiped out all enemies, they'd have nothing to fight.
If the Lupari ships can emit a pulse that stuns intruders, why did none of the pilots except Karvanista use it?
Evidently Karvanista is one of the most advanced pilots for the Lupari. He knows the ships inside out, so knows how they work and what can be used, hence why he was able to take remote control of the ship Bel had taken and bring it to the shield. Also, we don't know how quickly the Sontarans invaded and killed the Lupari; maybe they just didn't have enough time to do it for their own ship, let alone manage to do it for the entire fleet.
Why did the three Doctors need to telepathically communicate with each other? Before that scene all three Doctors knew what was happening to the other when they shifted between each other, why did they need to telepath with each other in that particular instance?
The Doctor is clearly shown to be quite unstable during those moments, though. Such as seeing the doors in Williamson's tunnels while on the Lupari ship. So the three of them using telepathy to communicate helps them clarify things without confusion as to who has seen what. Plus, they only seem to just know the general basics of what's happening to each other, but not specific details.
