Dangerous Seed - which sounds like a prequel to "The Omen" - is a nice vertical shooter that managed to wind up being unique enough in a crowded genre to make it memorable. You are flying through a variety of scenarios killing the ubiquitous space bugs.
Your spaceship is run (again) by the joystick and two buttons, fire and bomb (nothing unique there).
You start the game with three ships and each one has an energy bar to lose before you die. Each enemy shot that hits you costs you one mark on your energy bar - however, if you crash into an enemy bug/ship, you immediately lose that ship/die regardless of the status of your energy. You can also pick up energy capsules along the way to replenish your store. Something fairly unusual in the game is that your three ships are different from one another. Each one is larger and shoots different than the previous one. Also, in another effort to be different from other games, the bigger the ship is, the longer its energy bar (each ship can absorb one more hit than the ship before it). So, lose a ship and at least the next one is bigger, more powerful and more resilient. Along with the change in ships, comes a change in their bombs. Each ship has a different super weapon than the others - you'll probably drastically prefer one kind.
There other main thing that stands out for me in DS is the graphics. They aren't beautiful or groundbreaking, but they have done a great job of making them unique and "buggy". Yes, once again you are battling the damned space bugs. But here in DS, they just seem a little more organic. A little more alive. A little more jittery. Bugs move their arms and legs and wings and fire at you vertically, diagonally and horizontally. Lots of the enemy fire is larvae-like and squiggles a path toward you (guided-pupae)? It all adds up to a fun experience and an overall good time.