Hurricane

The Hurricane is a mechanic that appears when a track is so windy the wind is enough to affect bloons and monkeys in a major degree. It has the following effects:
 * First, all the bloons that move on the direction of the hurricane will be 2x faster. The bloons that move on the opposite direction will be 2x slower instead. The effect is less clear as the angle changes (just... imagine it).
 * Secondly, it'll eventually blow Hoverpads offscreen, so they're usually useless on tracks like this.
 * Thirdly, it'll also affect the flying towers' (like Monkey Ace, Heli Pilot,...) speed just like what it does with the bloons.
 * Unlike other "wind" effects in other games, projectiles won't be affected, because they're too fast.
 * Visibly, there'll be a strong wind effect that blows on the direction of the Hurricane.