Crossdown is a dastardly challenge map. 2 rows of bloons arrive on one track,1 goes to the loop while the other goes straight ahead. Every 15 rounds,The Turret Bloon comes.Popping it rewards you with 100 $ and A turret.Attaching the turret to a tower makes the tower very powerful. No Bosses appear here. If you let the Turret bloon pass you get 10 lives but lose 10 cash.If you dont have enough cash,You will lose lives.It takes about 21 seconds for a Red Bloon to get across the straight through while 26 including the loop.