You could simplify the back one, use just the two darkest colors, that would help the priority even more.
And it feels like the green plating should have a bit of shift to blue, the colors feel a little flat right now. Maybe even the same for the skin. If you look at Fusion’s Omega the darkest color for the skin is a straight violet.
hunter or hopper!
I made the main Fission, mostly a recolor just had to change shading on certain parts. I still wanna do the separate beam Fissions properly (more than just recolors).
Other than that, I will begin the Hunter because I have never seen a decent sprite of a Hunter and I want to see what it will look like 
Phlakey boy I’ll see what I can do with the colors now
I always replace the Brightest color with the 2nd Brightest, the 2nd Brightest with the 3rd Brightest… etc, except in reverse order (so it works properly). The darker area expands, and the whole thing seems to be behind things (Unless you’re doing Backgrounds, those get lighter due to atmospheric refraction).
Why not just change the Zeta/Omegas’ hand posture? I really like where this project is going though! Uh, one thing–the mochtroids were cloned from the baby, weren’t they? And to my understanding Phazon Metroids were heavily mutated Tallon Metroids. Sprites are gorgeous, but the timeline seems skewed.
Hey Dazzy. Thank you very much 
About the Metroids though, a lot of the Metroids evolution chart is debatable. This is mostly from what I can understand…
I think the Phazon Metroids are Metroid Eggs from Tallon IV infused with Phazon, which seems to make more sense because it will hatch to be a Miniroid, (which is why it would resemble an Infant Tallon Meroid), and the Miniroid would then grow into a Phazon Metroid, and somewhere along the lines gets turned into a Hopper Metroid. I don’t think it’s a mutated Tallon Metroid because that’s the how you result in Fission Metroids. I think Metroids grown on Tallon are Tallon Metroids, and since they can’t evolve properly there, they grow into Hunter Metroids.
I’m going to list the Metroid Hatcher as a heavily mutated breed of Hunter, because it was never specified how a Hatcher was formed either, and they both have similar shapes and tentacles.
The red Tallon Metroids I believe are a result of Infant Tallon Metroids being transported to Aether before they have the opportunity to evolve into Hunters. They turn red when they become Hunters anyway, so they just grow with a red membrane because their evolution gets all screwed up yet again from being
exposed to another environment.
I’m going to list Prime as an evolution of a Hopper Metroid, because of two things. Firstly, they look similar, look at the pointy head and the legs. Secondly, there were shells of Prime’s Exo form all over the Genesis Chamber on Phaaze. They were either “skins” shed by Metroid Prime, or there were more Primes on Phaaze who’s Core forms had hatched from their Exoskeletons and were floating around elsewhere on the planet when Samus was there. There were also Hopper Metroids on Phaaze, so I’m just listing it as such. Metroid Prime’s origins (and how Metroids are on Phaaze in the first place) are such a mystery which is why I love the Trilogy. So many things still leave you wondering :3
The Mochtroids were indeed a result of cloning the Baby, but I didn’t want to list specific individual metroids on here, just the evolution possibilities.
Anyway, here’s an update. A lot of palette changes, and some changes in the shading.
Phlake and Zurg what do you think now? I mostly did what you both suggested. And Daz what do you mean about the hand posture?
I’m pretty sure Corruption explicitly says they’re mutated Tallon Metroids. Note that the pirate labs on their homeworld have an area dedicated to the study of metroid evolutions, and there was a panel saying that metroids developed differently depending on two factors–infusions/mutagens, and their environments. Hence why the SR388 mutations haven’t been seen elsewhere for the most part, but that could also be extended to indicate that Fission Metroids A) were specific to Tallon IV, B) were specific to that particular Impact Crater, or C) were specific to Orange Phazon, which never interacted with metroids outside of the first Prime.
As far as the arms go, I just meant that if you moved how his arms are positioned it might make it easier to discern the ‘rear’ arm from the foreground arm.
Corruption does say that, but at the same time Corruption states that Miniroids transform into Phazon Metroids. I don’t think Fission Metroids were specific to the Impact Crater or Orange Phazon, because in the Trilogy version there are Fission Metroids all over the third level of Phazon Mines once you kill the Omega Pirate.
I’m not sure, there are too many complications with the actual evolution. The chart I’m making isn’t completely canon, I’m just going by what I can understand. Some of the mutations can’t really be explained as to why it happens… mostly the ones from the Prime Trilogy xD
The only confirmed evolution process out of Prime consists of very few…
Egg–Infant Tallon
Infant Tallon–Tallon
Tallon–Dark Tallon
Tallon–Hunter
I think those are the only ones that are actually proven…
http://metroid.wikia.com/wiki/Hunter_Metroid
http://metroid.wikia.com/wiki/Metroid_Hatcher
all the chains are on here
The Hunter Metroid scan says it is still in an adolescent form, but there is nothing known to us that follows after. The Hatcher says there on Wikitroid that it is preceded by a Phazon Metroid, but I don’t think that was ever confirmed.
I’m just assuming that the Hunter Metroid somehow can turn into a Hatcher.
You can take the colors pretty far with it still looking good-
Phlakes I’m trying to stick closer to the main turquoise color, but I see watcha mean. I’ll experiment some more
It’s really just the darkest shade that makes it feel a bit flat, it actually looks a bit greener than the midtones (it isn’t of course, but that’s pixel art for ya…).
Ahh, point about the miniroids.
However–
"Heavy exposure to Phazon energy has mutated this strain of Tallon Metroid. "
That’s pretty damn unambiguous. I fail to see how it doesn’t count as “proven” or “canon” when it’s explicitly stated beyond any doubt. When you factor in “Those that survive will grow quickly, becoming the feared parasites known throughout the cosmos as Phazon Metroids,” it becomes clear…
It obviously means that infant tallon metroids + new environment/infusion = miniroids → Phazon Metroids… I know I’m being nitpicky, but hey, that’s what I do.
ON TO MORE RELEVANT THINGS!
The purple(?) shading on the Omega definitely adds some more depth. Sticking to a palette is one thing, but as the sprites get bigger they need more shades and contrast. Otherwise you get congruity at the expense of it being extremely flat – and I honestly don’t think a more varied Omega would clash that badly. Even if it did, as they evolve, they change plenty already; a slight change in tint isn’t that inexplicable. If you look at their official art, parts of the Omega appears more green than the Gamma, for instance, who is more of a teal color.
At least, in my opinion. I am colorblind, so take that with a grain of salt, but it looks to me like early evolutions are pure teal and the later ones gain deeper green as well.
I hear ya Daz. It doesn’t specify whether or not the Phazon Troid is a result of a mutated Infant Tallon or a mutated mature Tallon. I’m just listing it as an evolved Miniroid, because I’m pretty sure a Miniroid is some sort of mutation from a Tallon Metroid anyway, which would explain why the Phazon Troid is listed as an evolution of both. Making a separate line would make the sheet look weird 
Anywho, how about these?
Some palette changes again on the shell. Also the darkest color for the membrane of the Red Tallon Metroid, which is now the same palette for the Hunter’s membrane, which currently has no teeth or tentacles :O_O:
Hunter looks interesting. Don’t they perpetually keep their long squid tentacles out though, or do they only appear when it attacks?
They’re always dangling, and they extend in attack.
Segmented sprite, perhaps?
Huh, that’s almost disappointing. I never really got a good look at them ingame, and the idea that it keeps them retracted as it flies around seems cool in a way… IDK, it just has a unique look to it without them, whereas with them it just looks like a space squid.
But hey, accuracy > coolness. ADD THOSE TENTAQUILLS.
Also, I just realized the fangs were missing. So maybe the sprite was just unfinished and I jumped the gun. Or maybe you honestly just forgot to add them. So either way… um…
Look, a distraction!
And no I didn’t forget the teeth or the tentacles I just didn’t do them yet xD
Say, when a Hunter latches onto you, do both tentacles latch or does just the one? 0_o
Just one, the other is busy holding its pimp cane.