Talk:The Sacrifice/@comment-96.55.213.62-20180615195821/@comment-181.168.216.104-20180616001625

The story goes that they made the (umbra) warframes first, but were unable to fully control them. You make them out of human experimentation with infestation after all, so obviously they will keep their emotions. The story says the sentient turned THESE warframes against the orokin, and the orokin responded by linking the LATER generations of warframes with the tenno to prevent it.

Despite it, the tenno also revolted after defeating the sentients because being naive isn't being stupid, and eventually they were all frozen and stored for later by lotus, when "the system needed them the most" AKA the present.

Their orokin connection makes them weak to the orokin's commands, hence why the warframes stop moving just like the dax, but that doesn't mean they can't be taken by surprise. If you can't tell them to stop, then they won't, good old loophole for people who MUST follow orders.