Vajrayana's claim is speed: where the bodhisattva path is measured in aeons, tantric methods claim Buddhahood in a single lifetime by using the energies of desire and aversion rather than suppressing them. The methods are correspondingly risky — the tradition's own literature is full of warnings — which is the stated reason they are transmitted under restriction rather than published. It is the dominant form in Tibet, Bhutan, Mongolia, and parts of Japan.