The active power
A little while before Quinn and the others arrived at Blade Island, there was a certain question that had been on their minds. 'If the Demon tier beast was so important to the Dalki, then wouldn't it be better to just kill it?'.
If they managed to kill the beast or at least one half of it, wouldn't that stop the Dalki from prolonging their life? Wouldn't it turn into a 'simple' waiting game for the human race? All they would have to do would be to outlast the Dalki until they would die by reaching the end of their lifespans!
However, according to Richard Eno, doing so was practically impossible. In the first place the Demon tier beast used to be a two headed dragon, which had the ability to split itself into two. This was what it had done when originally fighting against the vampires.