EDIT: Dammit Aisha, and I took all this time typing this-- and for a better guide too that trivializes mine :V
I'm not entirely sure. Here's what I've figured out so far:
In Giga Wing, you don't even gain points for collecting medals. Your medal count is your multiplier. You'll notice that when you start the game, each popcorn enemy is only worth 200 points. Collect a couple medals, they're worth 1000 or so each. Your medal count is directly related to your multiplier. You'll see that the gain works like this-- the number you get on-screen as you collect medals is your 'actual' medal count, but many medals are worth more than 1 point. Most are worth 5. The only medals that are worth 1 are the ones you get from using the reflect barrier.
So say you collected 5 5-point medals. Your counter on-screen will say +25.
However, your multiplier is that number right under the score. You'll notice that that number jumps up really fast, and that's because your medal count is
added to the multiplier every time you collect a medal.
For example, if you were collecting 5-point medals:
Medal 1: Count = 5, Multiplier = x5
Medal 2: Count = 10, Multiplier = x15
Medal 3: Count = 15, Multiplier = x30
Medal 4: Count = 20, Multiplier = x50
Medal 5: Count = 25, Multiplier = x75
and so on. That's why your Reflect Barrier is mega-valuable in this game and you should do your best to remember the best times to use it. For example, if you're using Ruby, the first stage should have a bunch of larger airplanes that shoot these dense waves of bullet-strings at you. Reflect the bullets at them, as well as as many other bullets you can. This will cause a bunch of 1-point medals to fall. This is where your multiplier will spike.
So say you had your x75 multiplier from the earlier example. Now let's see what happens if you were to collect... say, 10 1-point medals:
Medal 1: Count = 26, Multiplier = x101
Medal 2: Count = 27, Multiplier = x128
Medal 3: Count = 28, Multiplier = x156
Medal 4: Count = 29, Multiplier = x185
Medal 5: Count = 30, Multiplier = x215
Medal 6: Count = 31, Multiplier = x246
Medal 7: Count = 32, Multiplier = x278
Medal 8: Count = 33, Multiplier = x311
Medal 9: Count = 34, Multiplier = x345
Medal 10: Count = 35, Multiplier = x380
So you can understand why your score skyrockets, especially when your medal count is in the thousands-- which is not hard to do at all, since you'll be collecting medals like crazy in this game.
This is only a very small-scale example, because I'm horrible at even basic math and I didn't want to hurt myself
What you do have to consider is risk over reward, though. Don't go getting yourself killed over a multiplier boost, because once you die, your medal count that you worked for? Gone. So while your multiplier might stay the same, your ability to boost your multiplier is fucked.
So say your multiplier is at x150000. I'll use a random medal count here....
Medal 1: Count = 2345, Multiplier = x152345
Medal 2: Count = 2346, Multiplier = x154691
*death*
Medal 1: Count = 5, Multiplier = x154696
Medal 2: Count = 10, Multiplier = x154706
Medal 3: Count = 15, Multiplier = x154721
So you can understand why dying ruins your score. You may think that it's fine to die because you keep your multiplier, but you'll notice that
your score gain will stagnate drastically when you die, because you can't keep adding to the multiplier. It is always better to live to increase your multiplier at a slower rate than it is to die trying to get a huge multiplier bonus.
That's what I've got, so far. Don't kill me if I'm wrong @_@
