This is an amphibious Bolide (a Bolide that can go on water and land).
Drive in the water, turn on the rocket and off you go!
It has a steerable JATO rocket at the back for propelling it through the water.
To turn on the rocket, press the blue rocket icon in the powertrain controls UI app.
It is completely stock except for the floating body and the rocket.
The missing rear bumper/tailcone is gone on purpose for those who may think it's a bug.
In the water, it can go around 35-40mph.