In its latest novel, Force is the key to countless powers - primarily abilities that allow them to exert their will over others, or to lash out in anger and aggression. That isn't to say the most skilled Sith have no subtlety; Palpatine spent years operating in the shadows, using the Force with care and precision so he didn't attract the attention of the Jedi.
But Palpatine's favorite trick - indeed, his trademark move - is undeniably his flashiest: Force Lightning. The prequels and the original trilogy showed Palpatine and other Sith using Force Lightning on isolated targets, but Palpatine prefers to use Force Lightning.
Queen's Hope is quite an unusual Star Wars book, in that it contains rare scenes from Palpatine's own perspective. It's set shortly after the beginning of the Clone Wars, and in one scene a furious Palpatine slips into his sanctum to unleash Force Lightning at a Sith relic designed to absorb his wrath so he doesn't give himself away to the Jedi. The concept is a fascinating one, suggesting Force Lightning is essentially a manifestation of a Sith's anger and rage, and that expending it in this way acts as something akin to an emotional release. If that is indeed the case, it's easy to see how a Sith could grow almost addicted to the rush that comes from unleashing Force Lightning.
This may explain why Darth Maul never used Force Lightning; Palpatine envisioned Maul as a brutal weapon to be used against the Jedi, and he stoked his apprentice's anger and rage. Palpatine only wanted Maul to have one release for his wrath - brutal murder. Presumably, then, Darth Sidious chose not to teach Maul how to generate Force Lightning. In contrast, Palpatine certainly taught Dooku the trick, but Dooku was expected to perform a different role, potentially to be a distraction for the Jedi who thought he might be the Sith Lord. In that case, it was in Palpatine's interests for Dooku to possess the power.
This subtly reinterprets the end of Star Wars: The Rise of Skywalker, suggesting Palpatine may well not have been lying when he claimed to be channeling all the Sith; that would explain why there is now no limit to his hatred, meaning he can blast out a fully-fledged Force Storm. But, of course, the best Jedi are able to deflect Force Lightning, and even reflect it back at their enemy. Palpatine, who had essentially become a conduit for unlimited anger, could not shut it down, and so was destroyed. It's ironic that the very hatred that fuels the Sith seems to have brought an end to their lineage at the end of the main Star Wars Skywalker saga.
