Sunflares can be done in a couple of different ways. Of course, I've done neither, but they're hardly impossible. There's the method in which the player's screen "glares up" (with a force-blinding-like effect) as their central position gets closer to the sun, which isn't difficult so long as you consider it as you build a level. The other method is the overobsessive pseudorealistic method using sprites up the wazoo. GuNbOy was experimenting with it last I heard, but all I ever saw of it was a picture of it more or less working in a large open area. I'm not sure how having architecture in the way would affect the effect, but, I presume, it would be more trouble than it's worth.
Rain, on the other (similar) hand, is (more) doable. It's never been done exceptionally well, bur it's doable. I'll let someone else handle that, though.
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...Jabberwocky.X...
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~Wocky
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