is everything in music limited to those four clefs? that implies that there is theoretically a limit to how high or low you can make what you're writing, and while that is true when it comes to what pitches a human can hear, i think that there should be at least two or three other clefs to represent those notes that are either too low (for example, the octobass; how the heckydizzle do octobass players read music?) or too high to hear. this is probably a deep and stupid question, but i would kinda like to hear your thoughts and opinionés on this.
if you put "8vb" above the staff it means you are supposed to play the thing an octave lower than it's written. you can do 16vb too. or 8va (above) or 16va. even use higher numbers. or you could just write "play 2 octaves higher" in whatever native language your reader(s) are familiar with