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evil design; crafty plan; plot
奸計を巡らせて政敵を陥れようとした。
They devised a crafty plan to entrap their political rival.
敵の奸計を見破り反撃に転じた。
They saw through the enemy's plot and counterattacked.
奸計に気づかず信用してしまった。
Unaware of the plot, they ended up trusting them.