Hello Greg,
Back in the 2007 story arc, one of the plot points was that Hydraxon had been killed long before the present story, and the Hydraxon that we saw was a copy made by the Mask of Life, transforming the dying Matoran Dekar into a copy of Hydraxon. Then, years later, when it was revealed that the Red Star was meant to revive deceased beings, you specified that the original Hydraxon had been revived on the Red Star, meaning that there were two versions of him alive at the same time.
When you originally decided to have the original Hydraxon be dead back in 2007, were you leaving yourself a loose thread to possibly have the two versions of Hydraxon meet each other in the future? Had you decided on the Red Star’s revival function that early, or was Hydraxon’s death an unrelated idea?