Load Buddha was enlightened by understanding the eternal law (of patichchasamuthpada)
OR four Noble truth, and Moksha.
OR delusion and how to avoid it.
OR Life is a dream and how to awake from it.
For explaining this he (and his followers) used several methods according to what the listener already believed.
Tantra-meditation and ritual practices that seeks to channel the divine energy of the macrocosm or godhead into the human microcosmThantra
Bhairav Tantra-it briefly presents 112 meditation methods or centering techniques (dharanas). Bhairav Tantra
These include several variants of
-breath awareness,(Ānāpānasati (Pali; Sanskrit ānāpānasmṛti, meaning "mindfulness of breathing") is a form of Buddhist meditation now common to Tibetan, Zen, Tiantai and Theravada Buddhism as well as Western-based mindfulness programs.)
-concentration on various centers in the body,(Sathipattana)
-imagination and visualization and contemplation through each of the senses.(Five Aggregates)
- Moksha - Identity with Shiva(the deity who represents Universal Consciousness) - Link Kashmir Shaivism
Dilution is I - (My Self) concept. To remove this need systematic process. Tantra images are intermediate steps of some traditions.