No problem. Just think about a gameplay mechanic that would be fun and unique and change the design based on that.
You mentioned before you wanted your enemy to roll, if you wished to stick with that idea, you could have redesigned the enemy to look more like it's going to roll around. Even Retro Studio did this. For example, the concept art for Skelly Rex from DKCR shows that they originally had round heads. They were changed to have long flat heads later in the game to show that you have to jump on them an not roll into them. So it's no big deal to have an idea that needs some changing. Even the greatest video game companies do it.
Any other advise I could give? Hm. Well I came up with a DKC enemy once myself. I wanted an enemy that you could throw a barrel at and it would stick to the top of it's head or body. You could safely jump on top of the barrel that's stuck on it's head and ride the enemy across dangerous paths.
Based on what I just said, I came up with a slimy slug that would use the barrel you threw as a shell (becoming a barrel snail)
See before I decided what kind of animal it was I thought about a gameplay mechanic first. Now you don't have to do it in that order, but it makes enemy design much easier.
Now that I'm done blathering, I'll discuss your enemy!
Kahmeleon should probably still blend into it's surroundings. That was a good idea, it makes sense a chameleon should do that. I was advising he shouldn't both attack with his tongue and roll. It should just be one of those things. I'll leave that up to you. If he is to roll around I suggest Kahmeleon be on all fours to imply he'd coil up. If he attacks with his tongue, you should make his head pretty big to imply an attack woulf come from there. (Notice how big a Klaptraps head is?)
You mentioned before you wanted your enemy to roll, if you wished to stick with that idea, you could have redesigned the enemy to look more like it's going to roll around. Even Retro Studio did this. For example, the concept art for Skelly Rex from DKCR shows that they originally had round heads. They were changed to have long flat heads later in the game to show that you have to jump on them an not roll into them. So it's no big deal to have an idea that needs some changing. Even the greatest video game companies do it.
Any other advise I could give? Hm. Well I came up with a DKC enemy once myself. I wanted an enemy that you could throw a barrel at and it would stick to the top of it's head or body. You could safely jump on top of the barrel that's stuck on it's head and ride the enemy across dangerous paths.
Based on what I just said, I came up with a slimy slug that would use the barrel you threw as a shell (becoming a barrel snail)
See before I decided what kind of animal it was I thought about a gameplay mechanic first. Now you don't have to do it in that order, but it makes enemy design much easier.
Now that I'm done blathering, I'll discuss your enemy!
Kahmeleon should probably still blend into it's surroundings. That was a good idea, it makes sense a chameleon should do that. I was advising he shouldn't both attack with his tongue and roll. It should just be one of those things. I'll leave that up to you. If he is to roll around I suggest Kahmeleon be on all fours to imply he'd coil up. If he attacks with his tongue, you should make his head pretty big to imply an attack woulf come from there. (Notice how big a Klaptraps head is?)