Okay, so, apparently, you can cast multiple spells instantaneously for the cost of one spell if you don't move after entering the Dreamscape.
Quote:
[HP:100%] [ME: 45%] [PE:100%]
> c 'create food
You start to concentrate.
[HP:100%] [ME: 45%] [PE:100%]
> !
You start to concentrate.
[HP:100%] [ME: 45%] [PE:100%]
> !
You start to concentrate.
[HP:100%] [ME: 45%] [PE:100%]
> !
You start to concentrate.
[HP:100%] [ME: 45%] [PE:100%]
> !
You start to concentrate.
[HP:100%] [ME: 45%] [PE:100%]
> !
!
You are too stunned to do that.
[HP:100%] [ME: 45%] [PE:100%]
> !
You are too stunned to do that.
[HP:100%] [ME: 45%] [PE:100%]
> You are too stunned to do that.
[HP:100%] [ME: 45%] [PE:100%]
>
You utter the words, 'qcandusahz yaae'.
A piece of pink birthday cake with white icing suddenly appears.
You utter the words, 'qcandusahz yaae'.
A piece of pink birthday cake with white icing suddenly appears.
You utter the words, 'qcandusahz yaae'.
A piece of pink birthday cake with white icing suddenly appears.
You utter the words, 'qcandusahz yaae'.
A piece of pink birthday cake with white icing suddenly appears.
You utter the words, 'qcandusahz yaae'.
A piece of pink birthday cake with white icing suddenly appears.
[HP:100%] [ME: 42%] [PE:100%]
Not sure how that works with other kinds of spells, but I can't see it being too different.