Board Thread:Questions and Answers/@comment-5919632-20130604005943/@comment-26871105-20150809094220

It doesn't require unsheathing to fully activate Anubis, as when sheathed it can still call to its current wielders, use its slicing ability, locking the sheath to prevent being used by unwanted individuals as well as sheathing itself even when the user is already unconscious.

Just that it seems to only be able to do the things it does normally in a lesser degree, as demonstrated by the fact he has to persuade people to open the sword before forcibly taking control over them after it's unsheathed. And it can only cut people's finger open across the sheath when closed instead of just cutting them off like what he would just do.

So I would imagine rats are just easier to control due to their lack of sophisticated intellect, which makes it possible to either control a group simultaneously, or he simply just need to take control of their leader which orders the others to transport the sword together with him. I would bet what actually happened was the latter.

Anubis only failed taking control over anything at the bottom of Nile river because nothing down there even has any intellegence.