Shield can now only be raised for a maximum of 4 seconds
However long the shield is raised the player then has to wait that long until they can raise the shield again
Shield can be raised for a minimum of 1s (ie. if a player taps RMB, the shield will do a 1s hold and then have a 1s delay before it can be used again)
Communicated via the on screen progress bar (aka compound bow)