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We present a multifunctional packaging technique for implantable microdevices. The packaging is composed of 3D printed bulk piezoelectric barium titanate (BaTiO3) ceramic with unique geometry shaped (i.e., regular convex polyhedrons; Platonic solid). The BaTiO3 ceramic provides not only a seamless packaging for essential electronics but also a power source for those electronics through the conversion of incoming ultrasound. Ultrasound has been an attractive powering source for many implantable microdevices [1]. However, most ultrasonic receivers are rectangular or disc, not in ideal form factors; ultrasound is often deflected within the path, and the miniature implants might shift and rotate, resulting in an angular misalignment. Tailoring a three-dimensional polyhedral architecture (i.e., Platonic solid) for an mm-scale ultrasonic receiver can dramatically enhance its omnidirectionality. Utilizing the 3D printing technique, we devised a dodecahedron shaped BaTiO3 ceramic with the center void space for electronics embodiment. As a proof of concept, an LC (inductor-capacitor pair) resonator is implemented as a representative implantable microdevice [2, 3]. The LC resonator has been utilized in physiological sensing by employing either a capacitive or inductive sensor. These sensors are typically powered by inductive coupling or batteries which can be impracticable when the implant is placed deep inside the tissues. Instead, the ultrasound-mediated interrogation scheme can compensate for these inadequacies. When ultrasound impacts the dodecahedron BaTiO3 ultrasonic receiver, it energizes the embedded LC oscillator, generating resonance radio frequency (RF) waves, which can be detected by an external antenna (Fig. 1).