The high-rank demons were fighting all over the place. For someone to control the abyss altar, they need to bind with it. The bonding is very quick if the abyss altar is ownerless. But there will be resistance that will prolong the bonding process if the previous owner hasn't given up control and is still alive.
The resistance can increase the bonding time to a matter of days but it depends on the difference in the spiritual strength of the previous owner and the aspiring owner. That's why anyone that is the current owner will be the target of all attacks. But the fight is more delicate than that.
