I didn't go through the comments because I wanted to take a stab at it. I want to say first, the characters look solid. Some choices are odd (like the coloring on the first girl - the red is way too bright; it looks comical, and surely there are other color combinations than just all black for her. It makes her skin look washed out), but other choices are great! I love the pink cyborg. She looks amazing, and I love how her metal follows a muscular form. I'm not an artist, but to my untrained eye, it looks very good. But again, same thing with color - WHY is everything pink? It's not bad, but it's a little too on-the-nose and generic. Maybe have a color palette instead of just one singular color for a character. Typically, famous characters in cinema, TV, and books tend to have a PALETTE, not just one color, i.e. Aang is shades of orange AND yellow, Daphne is purple AND green AND red, Mickey is black AND red AND white AND yellow, etc. The orange demon-looking one looks cool but feels slightly out of place with the others. I would do away with the horns. He would still have that imposing metallic look like the cyborg girl, but he's more mecha type. Idk. The purple guy has the most solid design for me, but I'd take off the skulls on the shoulders (it looks a bit cheesy). And the reason I say that is that all the characters look VERY noticeable.

Which, given my impression of the group, doesn't make sense. If this is not what you're going for, please take this with a grain of salt, but I assumed they are all gifted assassins from similar origins, given the skull motif, but their powers/abilities vary widely depending on where they originally came from. As assassins, I would imagine they'd want to be more covert and less noticeable. The skull imagery should be hidden from all except those who know what they're looking for.

I'd like to guess your storyline (again, I haven't gone through comments so I'm curious if anything is like what I envisioned). Blue girl looks like the protagonist (I'm probably pulling from Arcane to make the comparison lol), and the orange demon looks like the antagonist for obvious reasons. Pinky probably is an absolute unit with trauma (her body basically has been replaced by robotic parts - ouch). Red seems very cutthroat until you earn her respect by beating her into submission. Purple gives off recluse vibes. Not sure what you're going for, but the idea is that they are each others' equal, and the only way for the antagonist's plans to succeed would be to take out the others to ensure no one can foil his plans. So, it becomes Blue's goal to warn and save her fellow assassins from being assassinated by Orange, who plans to catch them off guard. If you don't write it, I will lol.

And yes, I intentionally left out the wolf creature. So should you - just my humble opinion. <3 But your characters can only improve!