Bhishma said By penances, by Brahmacharya, by weapons, and by (physical) power, applied with or without the help of deceit, the Kshatriyas should be vanquished.
भीष्म उवाच तपसा ब्रह्मचर्येण शस्त्रेण च बलेन च। अमायया मायया च नियन्तव्यं तदा भवेत्॥