Who knew someone so big could be so stealthy

Between Giant Wasp doing a Basic Thwart and Giant Help, Nadia is uniquely suited to use Stealth Training. Her abilities to divide her Thwarting means she will always be able to exactly defeat a side scheme.

You could add One Way or Another and/or Sentry to make sure side schemes are around but as I play mostly 4 player games, between player side schemes and the extra encounter cards you will usually see one. The 4 player games is also why I play Even the Odds and have 3 copies of Skilled Investigator.