Does the defensive duelist feat allow PC to know whether using AC boost would 100% avoid hit?

Does Land Vehicles proficiency apply to mounts?

Stealth movement is it 2/3 speed per overland movement or full speed during combat?

If a creature is dancing from Otto’s Irresistible dance, is it able to use it’s Legendary Actions?

Guardian of faith “moves to a space” mean can move out on turn and not take damage?