(edited by Avariz.8241)
Elder Dragon Power and Will
Elder dragon power is inverse proportional to tyria magic. This is a recycling process switching back and forth between elder dragon power and tyria magic. When elder dragon power is at maximum then tyrian magic is at minimum. When elder dragon power is at minimum then tyrian magic is at maximum.
Creation of the Bloodstones can and has disrupted this recycling process when large portion of tyria’s magic was locked/sealed away in the bloodstones. This can only mean the elder dragons are weaker than they were before bloodstones creation. Could the introduction of the human gods in to Tyria rebalance over all magic in Tyria. The loss of magic locked away in the bloodstones being made up by human gods’ power.
By leaving Tyria could the human gods be trying to deprived the elder dragons from a new source of magic and thus keeping the elder dragon weak. This would make the job for the human fighting the elder dragons easier.