Ragdolls are simple on the outside but detailed on the inside. You can siphon their blood and replace it with nitroglycerine. You can submerge their head and cause brain damage by asphyxiation. Think of something horrible, and you can probably do it in People Playground. Afterwards, you could even hook them up to an ECG and blood supply to try to get them back on their feet.
Every object in the game has its own physical properties: weight, sharpness, thermal and electrical conductivity, ferromagnetism, heat capacity, bullet resistance, and so on. The game simulates temperature, heat transfer through objects and through the air, electricity, and rigid body dynamics. All these systems combined make for emergent gameplay. You may experience behaviour that was never explicitly implemented.
Mutilation aside, you are encouraged to build interesting contraptions or download them from the Steam Workshop. Construct airplanes, walkers, impenetrable bases, automatic doors, shields, computers, unholy weaponry - it's up to you!
Once you get bored of the limited amount of items, you may download one of many Workshop mods and addons to expand the toy box, or you could make your own.
