Summary

• Maul and Dooku were both trained by Palpatine but were never able to overthrow him, instead serving as pawns in his grand plan for the Sith Empire's return.
• Maul specialized in assassination and was not taught powerful dark side abilities, while Dooku was trained as a leader and had a wider range of skills including Force lightning.
• Both Maul and Dooku were ultimately deceived by Palpatine and prevented from fulfilling their true potential as Sith Lords. Dooku had more potential to become a Sith Master, but Maul had greater hatred and conviction.

Darth Maul and Count Dooku are some of the most iconic Sith from any Star Wars trilogy since both of them were hand-picked and trained by Palpatine himself. Having been trained to become Sith Lords, both Maul and Dooku sought to gain more power under Sidious while simultaneously looking to overthrow him. Toward the end of the Clone Wars, Dooku and Maul did actually meet each other in canon in the Son of Dathomir comics by Jeremy Barlow. And while the comics made it clear who was more powerful than the other, a more detailed approach is needed to determine who has more potential as a Sith Lord.
Despite both of them boasting enormous power in the dark side, Maul and Dooku pale in comparison to the dozens of Sith Lords in canon. Neither of them managed to overthrow Palpatine and claim their place on the top. Instead, both of them were mere tools in Palpatine's grand scheme for the Sith Empire’s return. The Sith Master of any given era must utilize hatred and deception in order to dominate other wielders of the dark side, whereas Maul and Dooku and a love/hate relationship with Palpatine. They needed his knowledge of the dark side in order to grow stronger, but they also hated him for how he treated them.

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