This month's "Plug and play" article is a 2D game that has the player flying a plane, fighting against 5 different enemies that attack him in 10 different waves. It all starts easy, with enemies that don't fire at all, but must be avoided or shot.
The second wave brings in new enemies that fire from time to time. If you get hit, you can run into the shield powerup to increase your armor.
Things get more and more complicated as the following enemies are introduced; they fire more and more often.
The sixth wave includes various enemies flying at the same time; from now on, the enemies will come in greater and greater numbers, trying to make player's life as difficult as possible.
Nevertheless, a decent gamer will have no problems finishing the 10th level; here's the proof that I am a decent gamer (or at least a cheater):
The code is very well commented, as always.