Overlord is definitely a keystone for that specific flavor of power fantasy, where overwhelming strength is paired with a chillingly pragmatic and often ruthless intellect. When I look for similar series, I find the appeal isn't just about an overpowered main character, but about how that power is wielded—coldly, strategically, and often for ambitions that lean toward conquest or world-shaping control, rather than heroism.
One immediate recommendation is 'The Saga of Tanya the Evil'. The protagonist, Tanya, is a brilliant and ruthless tactician reincarnated into a magical World War I-esque setting. Her powers are formidable, but the true focus is on her Machiavellian strategies to climb the military ranks and defy the entity she calls 'Being X'. The series masterfully blends magical warfare with dark political and military maneuvering, delivering a protagonist whose calculating cruelty is a direct survival mechanism. It shares that cerebral, amoral core with Ainz Ooal Gown's actions.
For a different angle, 'Code Geass' belongs in this conversation. Lelouch vi Britannia's Geass power—the absolute command to obey—is incredibly potent, but the series is a labyrinth of political intrigue, grand strategy, and moral compromise. Lelouch is a chessmaster who operates from the shadows, using his intellect and his power to orchestrate a rebellion, sacrificing pawns and his own humanity along the way. The tension comes from the psychological weight of his strategies and the constant risk of his plans unraveling.
Another fascinating, though sometimes slower-paced, example is 'Log Horizon'. Shiroe isn't overpowered in a raw destructive sense; his strength lies in his brilliant strategic mind, earning him the nickname 'The Villain in Glasses'. The series delves deep into the socio-political rebuilding of a trapped game world, focusing on economics, governance, and psychological warfare. It captures the administrative and strategic darkness of building a new order, which feels akin to Nazarick's nation-building efforts. The darkness here is systemic and intellectual, rather than overtly violent.
For a pure, unfiltered dose of an overpowered being with a detached, almost alien perspective, 'That Time I Got Reincarnated as a Slime' might seem like an odd fit due to its generally cheerful tone. However, Rimuru Tempest's evolution into a Demon Lord involves calculated decisions, political alliances, and displays of terrifying power that remind rivals he is not to be trifled with. Moments like the annihilation of the Falmuth army showcase a strategic and devastating application of power that echoes the威慑 of Ainz. The tone is lighter, but the underlying capacity for ruthless, world-altering strategy is absolutely present and grows more prominent as the story progresses.
Finding these series is like piecing together a specific puzzle where power, intellect, and a willingness to operate in moral grey areas intersect. Each offers a distinct flavor of that strategic darkness, from the military chessboard of Tanya to the political theater of Lelouch. It's the cerebral chill of watching a perfect, amoral plan unfold that really ties them all together for me.