There was no time to marvel at the grotesque remains of the creature, though, as he had to catch up to Albus, who must have now entered the next room. Astor looked for the door but could find none; it was possible that Albus may have apparated, but then why enter a room just to disappear out of it? Astor puzzled over this for some time until he noticed the trap door underneath the skeleton of Kerberos. It could be entered freely by stepping inside the ribcage of the colossal remains, and it opened easily. It was without a lock and did not need to be forced open. Underneath the door was a stone staircase leading to a dark abyss. With no torch or spell to light his way, Astor had to enter blindly, hoping there would be some lighted passage at the bottom. As he descended the staircase, he had the disconcerting thought that a step would be missing, his foot would touch black nothingness, and he would fall to his death at the bottom of some pit. A cold draft gave him a chill; he was reminded of his entrapment in the catacombs and the ghastly spiders that haunted those underground passages.