Yoshi, Parakarry, Bowser and original unrelated characters

[Chris2Balls [:B]]

it just looks like low-res digital art to me, and not pixel art so to speak... apart from the two last pieces. their outlines could however be better.
my faves are the rocket mongoose thing and the dragon underneath.
i also have the strong impression that you are afraid of destroying the lineart for your pieces. another impression i have is a strong sense of déjà vu in terms of style and content.
there are a lot inconsistencies in your bowser, especially when it comes to the shell's shape considering the angle at which we see him, and his tail seems a little out of place and the spikes' angle do not follow the tail's shape and angle; there also seems to be an issue with bowser's legs and feet, the angle of the feet and the representation of the fold of the leg... and because of these, despite your good shading, volume is not conveyed effectively.
i'm being a bit more demanding than with others since you seem to draw pretty well :p
you can make colour palettes arbitrary if you like, but hue/ saturation shifting is usually due to conveying the colour of the primary or secondary light sources and its/their repercussion on the material affected through its properties (of the material and the light).

it'd be nice if you presented yourself in the new arrival topic, so that we have a better idea of who you are what you like etc and so that we can welcome you in a more appropriate manner!
oh and i'm moving this into the creativity (creative zone/creativity) subsub forum!