Der Warp ist eigentlich eher eine 40K-Sache. Anfangs gab es doch bei Fantasy nur das Reich des Chaos? Die Alten, sind die nicht auch erst später so eingebaut worden?
1988 wurden sie "die Alten Slann" (the Old Slann) genannt und sie reisten durch den "Warpraum" (warpspace).
Quelle: Realm of Chaos - Slaves to Darkness, S.10
The Old Slann travelled by means of interdimensional gateways, spanning the distances between the stars by travelling through 'warpspace', a parallel dimension which connects all points in the material universe. One of their first tasks upon arriving on the World was to set up a pair of gateways, one at each pole of the planet, to allow them to come and go as they pleased.
Warpspace, however, was not an empty void, but was composed of a form of power wholly alien to the material universe. It was inhabited by entities who were equally alien. As their great ships travelled through warpspace the Old Slann protected themselves with powerful enchantments, but eventually something went dreadfully wrong.
... etc. pp.