All it takes is a creative and analytical mind really. Also a sharp eye.
Assess what is going on, and break things down.
Possessed by Phoenix is a survival card that is split into 4 stages.
In the first stage the magic circles spawn on the left and right sides of the player's position, and if either the left or right side would be spawning off screen, then the position is adjusted so that both circles stay on the screen. It appears that one layer of the bullets spawn in a cross shape, and the 2nd layer also in a cross shape, but revolves slowly.
In the 2nd stage, the magic circles spawn continuously. Arrow head bullets are shot from the circles directly at the player, and the angle between the circle and the player + 72 degrees (and so on). Each shot consists of 4 layers, the first being the fastest and the last being the slowest.
In the 3rd stage, the magic circles spawn slowly at first, and then speed up. Bubble bullets are shot in the 8 directions which then split into 4 medium sized bullets in random directions which then split immediately into 3 small bullets which then split into 2 tiny bullets.
The last stage seems similar to the 3rd stage except that every other magic circle spawns purple circle bullets in 8 directions, with one of them aimed at the player.
Heaven's Dragon: Source of Rain seems alot easier
The screen seems to be split into about 11 parts, with every other occupied by the blue energy bullets. The bullets are then shot down from above, probably with a random x value within the space that they are allowed to be in, and then decelerate. The energy bullets in the middle columns turn into rice bullets upon slowing down, and are aimed straight at the player. The ones on the far left and right spawn energy bullets at a faster rate, and turn into those arrow bullets that then rotate.
That Mushihimesama one seems ridiculous but is probably even easier to program that the above two.
However, there's so much stuff going on I can't tell. I'm assuming that the ring of bullets in the beginning shoot those different bullets at a constant rate at the same angle. The ring of bullets then shrinks, expands, moves, and etc., changing the flow of the bullets.
On a different note, you should never underestimate yourself. If you tell yourself that you cant do it, then you wont be able to. Don't think too hard.
When in trouble: Assess the situation, break down the problem, analyze the possible solutions, formulate a plan, and then boldly follow through with it.
It's ok to skip a few steps though~
Now I did a bit of the thinking for you. Now all you need is a bit of creative programming.
