You should probably get ready for some trouble...
Kagero is amoung rare kind of Ninjas serving that she is a woman. She spent her years as her Grandfather’s pupil until he was killed by her major enemy, the Kawagami. She fought with Tsimbaro a trusted friend until he disappeered. She now is a Ninja Wanderer following where her feet take her.
The spirit of a creature trapped in amber cannot escape to it’s afterlife / next incarnation / whatever.
Such trapped spirits can be contacted by those who know the right rituals and magical power derived from them – typically the power to control one individual of that species.
Can by quite powerful if the creature is a colony insect (ant, bee, wasp, etc) – simply control the queen and you command the whole colony.