Death
Solin had previously planned to go to Hillstown and take the humans that were in that city as puppets for the dark race. But he was once again stopped by the other supreme figures of the dark race.
According to them, they had to be extremely cautious of the sea race. Since it seemed that the sea race was sending over more powerful sea monsters as time went by, it was clear that at some point in time,a see monster that was already in the divine rank would definitely appear.
If something like that happened, it was going to be better if they dealt with it on time. And in order to make sure that they did not spend that much energy in dealing with the sea monster that would have come over, they would have to collaborate, all four of them at the same time.