Not a straight fight (as, I think, Mimic would stomp on Colossus)
Exiles Mimic's power = Wolverine, Deadpool, Northstar, Cyclops & Colossus (all at 50% power)
I'm wondering about the durability Vs claws factor.
A lot of people question whether Wolverine can cut Colossus ... most say he can't because he doesn't have enough strength.
Now Mimic, in metal form, has half of Colossus's strength/durability.
He also has Wolverine's, denser than human bone claws.
So when in metal form his bones would be almost equal to Colossus' bone strength.
Bone strength >>>> skin strength
As Mimic's claws are made from this bone, I think they should be capable of slicing straight through Colossus like Wolverine's bone claws through a low durability superhuman (like Spider-Man or someone)
That was kinda my point, unless he has something that is more durable then Colossus I don't see him cutting into him without possibly taking damage himself.
Your right though, by all logic Mimic should generate enough force to perice Colossus skin. Still going to be hard to prove, even though I feel he could do it.
Didn't those claws break on several occassions? As I recall, Hyperion broke his claws + hand (kinda like squeezing an empty can) but I am almost sure they also broke in a fight, either against Iron Man, or against Namor or someone else with not-Hyperion-level durability.
So the situation is sort of like this.
Without backing the claw hit with superstrength or with Northstar's half speed, Mimic wouldn't hurt Colossus. If he does back it up, then there is enough momentum, but the claw material IMO is not tough enough to pierce Colossus' skin.
So that's my answer for the claw vs. steel skin thing.
All in all, Mimic DOES stomp Colossus, especially with the abilities you mentioned. However, claw vs. steel.....nah.
But....he looks like crap however, cause he's got deadpool's skin thing too
I also have the entire series and I don't really recall seeing them turn to metal....maybe when he was fighting the doombots before the Namor fight? I really can't recall them in any other form than bone. And seeing as how they were shown as bone in many times although since the very beginning of the series till he dies he has half of colossus' powers, I don't understand why sometimes they would be bone, and other times metal...doesn't sound right....I've seen them as bone when he was in steel form, so you can't say "they're metal when he's in steel form, and bone when he's normal", so........why would they be metal sometimes and bone other times?
The way I see it is that it was just something....of a graphical nature + perhaps the writer just didn't see it as something of great importance.