Sinistron (video game)
Sinistron is a side-scrolling, ship based shooter that was released for the TurboGrafx-16 in (year??).
The game is notable, among other things, for the ajustable armored jaws of the player's spacecraft. Opening the invincible jaws of the ship increases the spread of the player's shots but exposes the vulnerable cockpit.
Five power-ups exist in the game. The Vulcan flame cannon, crystal-pulse laser, and CHAOS missiles are weapon upgrades. There are also speed upgrades and invincible plasma droids which will flank your ship and absorp enemy pellets in much the same way as your ship's armored jaws.
Sinistron has only six levels, but has a steep increase in difficulty after the second level.