Ferox4 said:
Hmmmm.....? As I'm sure you've seen under the spell description for Expeditious Retreat it says, "There is no effect on other modes of movement, such as burrow, climb, fly or swim." As a DM I would probably NOT allow you tumble for 30' with the ER spell due to the above spell description. I'm sure someone else out there also has an opinion on this.....
The tumble skill works through normal movement, Ferox4. It doesn't modify your normal movement to fly, climb, burrow, or even "tumble movement." It adds a quality to normal movement.
The ambiguity, for me, is the portion of the skill description where it says you move "one half speed as part of normal movement." In 3.0 it was merely "up to 20'"...short and sweet. 1/2 speed, on the other hand, makes things murkier.
It may be a modification of the speed of your movement, on the order of the Track feat. Hence in one round, you'd move at 1/2 your speed, but because you're tumbling that movement is protected via the tumbling rules. In this case, since you're actually
moving more slowly, there would be no extra movement after the tumbling was over.
Or, it may merely represent an upper limit on how much of your movement can be tumbling. i.e. if you have a base speed of 30' you can move up to 1/2 of your speed as tumbling. This would leave you the other half of your speed as non-tumbling movement.
And in either case, it certainly seems like
Expeditious Retreat doubles tumbling movement, since it (for a creature with 30' move,) doubles normal movement, from which the tumbling parameters are derived. Unless there have been other clarifications...?