1. Fair enough, though I thought they didn't look as blocky in Gemini.
2. So this explains the extra blockiness? I kind of think it makes them harder to notice because you can't tell what they are. I think higher detail is good even if some pixels are left out when the sprite is farther away.
3. I'm not talking about the raycasting, that pretty much looks fine.
4. As far as performance goes, I might be interested in writing an optimized scaled sprite routine for you

1.  Oh, you're right about that.  
2.  True...I'll have to think about that one.  Part of the problem is sprites need to be 64 x 64...rather than using loads of memory that I can't afford, I wanted to used doubled 32x32 sprites, which end up being blocky anyways.  A 64 x 64 sprite, with its mask, costs 1 KB of memory, and a series of levels can have 7 objects and 4 enemies.  I'm open to suggestions
4.  That would be awesome.  It would need to be a masked one, and of course I'd need to look through the engine to figure out how to smoothly incorporate the routine

EDIT: What if I make enemies gray?  Would that help in telling one from the other?

64x64 sprites? O_o That does seems overkill, since most of the time you won't be seeing 3/4 of those pixels. Is that what Gemini used?

I think making it so enemies don't look like scaled-up 8x8 sprites will be a good start. But if I do make a scaled sprite routine, I would probably make it support black, white, gray, and transparent selected by the two bits for each pixel.

I personally like the look of the game so far. Hopefully you can find a solution to make the enemies look more detailled, assuming it won't have too much of an impact on performance. 32x32 sprite size maximum seems ok to me. 64 might be too much because when they're far away we won,t even distinguish what they are anyway.

I think textures should be gray, except wall outlines or the texture sides and enemies should be black.

Some of level 4!  New features:

* Herm Injection!
* Better map revealing: more is revealed from exploring, and doors have a symbol different from walls
* Health Bars!  (I did my best to make some health bars higher on the screen than others to help with distinguishing them, but it's not perfect)  By the way, these health bars have been extremely helpful in distinguishing enemies from other objects.
* Armor now reduces, rather than eliminates, damage taken, except for really weak enemies.  Armor will take 1/2 of the damage rounded up, and health will take the other half rounded down.

That is awesome. Love the way you did those health bars! And those enemies actually have faces

Nice Hot Dog. I like that texture a lot at the beginning.

What exactly is a "herm injection", btw?  I googled it and it returns this board as a result so

I made it up.  It's Health Armor Injection.