Explosions and other SFX in Game Boy games

[Martyr]

Bois, I'm currently planning a new personal project: a game restricted to Game Boy specifications. Something along the lines of Contra, but with an even more ludicrous story-line - think the Expendables meets Modern Warfare 2. Anyway, such a game would simply not feel right without things constantly exploding around you, right?

I could use some good examples of explosions and other effects which could come in handy when making such a game, since my spriting skills are not all that fantastic and I'd be restricted to a 4-colour palette with a limited amount of sprites (well, not really). No, I'm not going to 1-on-1 copy stuff, I always make my own content. Just need a shove in the right direction. Thanks.

[McSkippy]

EDIT:I know these won't suit a GB game, but I'm just giving out examples here.
 I'll give you two games that have incredible explosions and gameplay.
Alien Soldier(Genesis/Megadrive, 1995, Treasure)
This game is super hardcore. It's like if you stuff Gunstar Heroes, Contra, huge bosses, and aliens all into one game
this is the result. Their explosions are made with a big circle and shrink until a certain size(think of a balloon losing air), which is oldschool if your looking for that.
I can only demonstrate a video since no one likes to rip sprites from this game :http://www.youtube.com/watch?v=1XPOUxRmyv0

Metal Slug series(Arcade, SNK)
SNK is pretty top notch in their animations in their games. The explosions in their games are really exaggerated, but you know that's how SNK is.
Example: