Ragnus Magna is a world connected to both Hero Factory and Spherus Magna. It was created by the Great Beings when, before recorded history, Hero Factory found a way through space to Spherus Magna. The resulting war devastated both universes. So, as a safeguard, the Great Beings created a world in which both species could live peacefully. They then wiped the memories of all those who had been involved.
So, basically, work your creations into the storyline. Any Bionicle creations are welcome. Have fun building!