Ever since I finished my most recent project I've been thinking about what kind of game to do next and as it often happens, I had an idea I thought worth pursuing while in the shower. It occured totally randomly, maybe because I was really tired and it was early: I remembered playing LoZ: Link's Awakening and thinking that those enemies that you had to flip upside down with your shield before you could attack them or push them into a hole were cool, and that I should make a game where that was basically the only objective. Have I mentioned it was early? In LA, one type of spiky critter walked around aimlessly until you were directly horizontal or directly vertical to it when it would charge you where you could flip it (rendering the critter helpless), and another type just generally moved in your direction until you used your shield to push it into a hole. Also I need an excuse to start learning OpenGL and earn some more game coding knowledge and this could fit both of those. Somehow I managed to retain the idea for more than 10 minutes and from the original idea I came up with these points:

• Multiple "levels", the main premise being that you're a guy in a stage probably the size of the screen whose objective is to eliminate all the enemies on the screen. A basic level would consist of maybe four enemies, the player with his trusty shield, and a big hole in the middle of the screen. Get hit too much by spikeys or fall down the hole yourself and you lose. Smells like an opportunity to build a level editor as well.
• Almost certainly a variety of enemies, though I think the dominant type would be the sort that charges you; with lots of them it could become a challenge to flip one and scoot it towards the hole with your shield while avoiding others that line up with you and charge. Other enemies might include the sort of spikey you can't flip over, spikeys that shoot projectiles, ones that scramble back onto their feet quickly, etc. etc.
• Incorporate into the level editor all kinds of nifty obstacles and terrain - put holes anywhere you want, blocks (perhaps pushable?), different height levels, fixed emplacements that shoot projectiles at the player or anything that moves, mines...
• Setting/justification: Start at the bottom of a tower; for whatever reason you have to get up to the top of it and the only way to do that is to knock all the spikeys on the floor you're on down the holes to the floors you've presumably already passed/cleared, at which point you may ascend to the next floor. Not much, but it does involve lots of holes and stuff. Yeah.

So I think what I'm looking for is advice on whether or not this design idea is sensible enough to even pursue, and if so, in what ways it can be further fleshed out or improved. If you find the entire thing is a total wash, be kind, it's 1 in the morning. :) Thanks!

I say start on top of the tower! You have to finish a level to go down (for some reason), then when you go down the level is larger (because thats how towers are made) and some of the enemies you pushed down are there, waiting for revenge. With some new and more fearsome ones, of course.

what about a critter tower indeed?
you first have to climb up the tower, and you can only make your way by killing the spikeys. But once at the top of the tower, you find the Diamond Mother of Critters, which you have to push through holes through the rest of the tower to drag out, and suddendly, there is critters and spikeys everywhere in the tower. You have to kill the spikeys and push the critters in holes in order to clear the room and be able to turn the Diamond Mother of Critters through the hole and down to the next level.

Maybe you can imagine a way to program an infinite number of towers with increasing number of levels to go through?

What powerups do you plan to put there?(you got to have powerups)

could be muscle enhancer for a short period of time? that way you can push back the critters and spikeys without upturning them first? Or maybe some sort of magic power which reduces the size of all creatures, which makes them easier to upturn, move, kill, or outrun?
maybe you could add some sort of Anti-Critter Spray? It would spray all over the level and kill all of the spikeys, or of the critters in one go?

As for the level configuration, I think maybe a particular tower could have maze-like configuration, which would force the player to drag the critters one by one before being able to drag the Diamond Mother of All Critters through the hole?

Or maybe you can give some sort of back story to the whole thing? Both the Critters and the Spikeys are of the same specie, only the Critters are immature? BUt the critters have some sort of valuable chemical component in the belly, which burns them through if you slash them. SO you have to upturn the critters, but can slash the spikeys. The goal of the game is to get the most money from your tower trip (understand get as many upturned critters out of the tower) while it can last (understand critters only come out at night, and it leaves you with a limited time to go through as many levels as you dare.).

With this kind of game goal, you can have, say, one level of 25*25 squares, then one of 23*23, then 21*21, 19*19, 17*17, 15*15, 13*13, and so on and so forth until 3*3 squares, where it becomes EXTREMELY difficult to avoid the critters and to upturn them without pushing them against the wall and not being able to push them through the hole... But remember that, after that, you have to go down the tower, and push the upturned critters through the rest of the levels, upturning them each time...

Thanks for all the ideas, guys!

@AP: Since the root idea of this is more action-oriented, I think it'd be best to stay more along those lines by adding twists to the action, difficulty etc. The idea of puzzles isn't a bad idea at all, but not really what I'm going for all the same.

@Steadtler: Sounds cool! I'm sort of concerned about having 50 monsters fall with you down to the 25th level, honestly, but the idea of having increasing level sizes sounds fun because you could have some more fun with map creation while slowly introducing the player to the way the game works.

@Fournicolas: I like some of the powerup ideas, especially enhanced strength and size change...Also having some creatures whose challenge is being able to swipe at them as opposed to pushing them down the hole. Not sure about the "Diamond mother" though, sounds like it'd be rather difficult to manage and you'd have to accomodate for it in all the map designs. :D

@someboddy: Darn right you do!

Other power-up ideas: pick-up that allows you to quickly dash forward, pick-up that slows all the enemies down, maybe one that blasts a hole into the ground?