Discovery, Exploration
The Eldar quickly recognised the benefits of the inter-dimensional web way abandoned as a result of the defeat of the Old Ones and began to exploit it not only as a means of rapid travel between planets but more importantly as a place to indulge their taste for self-indulgent pleasure. They quickly realised that the psychic energy present in the warp could enhance their own desires and make anything they wanted become real. Very quickly the more decadent members of the Eldar civilisation formed Cults of Pleasure specifically intended to exploit this amazing phenomenon.