Isn't it just bi-copter?

No, it's a quadcopter setup, but simulated in a 2D world (I guess for simplicity). A bi-copter would require tiltrotors, which is different.

	▲	echoangle 3 hours ago \| parent [-]
		In 2D, a bi-rotor is equivalent to the quadcopter in the post. There are 2 thrusts you control to guide the thing.