It would be fun to "draw" any Megaman map by using LEGO bricks.
How many bricks will be need for it?
So, for my designs, it is 434 pieces for Mega Man standing, and 475 for Mega Man shooting.
However, it could certainly be far fewer pieces, as I made with two layers of 1 x ? plates (with the layers perpendicular to each other), and one layer of 1 x 1 tiles.
The reason I designed them this way is so that I could get black 1 x ? plates in bulk and easily recreate anything with them, and then everything would be consistent. But the piece count can certainly be reduced quite a lot of if you use plates of various sizes. It will still be a lot of 1 x 1 tiles on top, though. For the Super Mario one I made earlier, each brown tile was $0.79 EACH, so you may want to be sure you use the common colours whenever you can. You could try with other sizes of tiles, but I have a feeling it wouldn't look as good as if they are all 1 x 1... though now that I type this, I'm realizing, they do rotate slightly in their spot though, so maybe if you scale both dimensions by 2, and then use 2 x 2 tiles, those tiles would stay in place and should look better - but then it'd be bigger.
If you're doing 1 stud per pixel it's a lot. But more importantly, at that scale, do you have a warehouse to show it off in? Each LEGO stud is spaced 8mm apart, so a single NES screen would be roughly 2x2 meters (2 meters is over 6 ft for us heathens in the States).
If you wanted to do larger sprites without the "two layers of plates" that I did (like if you don't care about having a square or rectangular background), or entire screens, then luckily, there are
big LEGO pieces that are 16 x 16 studs, which are the perfect size for the common 16 x 16 pixel tiles that are used in some of our favourite consoles. You can connect multiple ones with Technic pins. It may be the simplest way to do sprite work, but I like the particular shapes that I am able to create with my plate-layering method.
A NES or Super NES screen, usually 256 x 224, would require 224 of the 16 x 16 blocks. The LEGO World Map has 40 of them, so you would have to buy six of those to have enough (and you'd have 16 extras). You'd also get a lot of round 1 x 1 tiles, which might be an interesting alternative to the square tiles. It wouldn't have the "slight rotation" problem since they're all circles so you wouldn't notice.