Azothath |
ummm... Phantom Steed:C3 is a legacy OGL spell. Tactical movement (in combat) is calculated/done differently than Overland travel. With a 'base speed'/Speed/'land movement rate' it moves as appropriate. It is only quasi-real, so as a spell effect it does not tire or rest.
You really want the Pathfinder/Rules forum rather than the Third-Party forum.