The Achturardackians were pioneers of sigil based magic, and their techniques for building glyphs, sigils and seals remain the foundation of magic inscription.
The relic of an old Sorcerer, the Glyph of Tarnos Krae is a window into the past.
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.