Complex sentence: The game is an active internet pastime for many amateur billiards enthusiasts all over the world (most notably from the USA and Europe) and has a small but dedicated following, many of which have been playing the game for many years.
Split into simpler sentences: The game is an active internet pastime for many amateur billiards enthusiasts all over the world (Most notably from the USA and Europe) and has a small but dedicated following. Many of which have been playing the game for many years.