User blog comment:CrimsonWarden/Time Stop and Time Stop Countermeasures/@comment-26952857-20160910005822/@comment-27008999-20160910035433

Ainz mentioned that everyone who's level 70 should have countermeasures to time magic. This includes Shalltear. The number one proof would be in the drama CD were none of the floor guardians were affected by time stop. Friendly fire is on in NW, so if they weren't immune they would stop as the magic would say. It's clear as day anyone in Nazarick who's level 70 and above would have it.