The Patriarch of Blood Clan hadn't seen Gabriel. However, he knew that Gabriel was trying to delay them for some reason. Instead of falling into that trap, he left the others to deal with the Undeads while he, along with some other leaders of the three Great Clans, went deeper into the Forbidden Land.
They were sure that Gabriel wasn't far from them. For him to cast this spell, he had to be somewhere around there!
They were right as well. When Gabriel cast that spell, he was indeed there. Unfortunately, he didn't need to stay there once the spell was successful!
The only reason he used this spell was to delay the three great clans so he could leave. He was in no mood to fight currently. Not only did he not have enough strength, but also there were no benefits to it.
In the end, he simply decided to leave the Forbidden Land for the time being.
