code/__DEFINES/vehicles.dm

RIDER_NEEDS_ARMS	Does our vehicle require arms to operate? Also used for piggybacking on humans to reserve arms on the rider
RIDER_NEEDS_LEGS	Do we need legs to ride this (checks against TRAIT_FLOORED)
UNBUCKLE_DISABLED_RIDER	If the rider is disabled or loses their needed limbs, do they fall off?
CAN_KIDNAP	Will this car kidnap people by ramming into them?

Define Details

Will this car kidnap people by ramming into them?

Does our vehicle require arms to operate? Also used for piggybacking on humans to reserve arms on the rider

Do we need legs to ride this (checks against TRAIT_FLOORED)

If the rider is disabled or loses their needed limbs, do they fall off?