Hey littlemocguy check your inbox
On topic:If you go to bionicle.com and look up krana xa-kal
it's power is to "release the bahrag"and it must come in contact
with the bahrag.My friend told me that makuta tricked the
bohrok kal into stealing the nuva symbols so he could defeat them.
So I have two theories
-My friends theory that i'm not going to repeat
-The bohrok kal actually release the swarm.
Hope this helps
Edit:BFT,the vahi slows down time