How to create a "multi bit pin" for a schematic symbol in Eagle PCB?
As far as I know, you can't assign multiple signals to one pin in Eagle, even if they have a common base name.  How would you be able to show the individual pin numbers on the part?

However to avoid clutter in a schematic, you can create busses as shown below:



In the Name dialog, the nets are separated by commas, in this case EN,VALVE[0..11].  But you still have to have an individual pin for each net.