Posting here incase others hadn't seen this article:
http://www.avclub.com/article/sentinels-multiverse-pays-tribute-convoluted-comic-222507
I have never heard of Ambush Bug but I'm sure going to look him up now. I had thought Morph/Deadpool was the inspiration for Guise but I was wrong.
thanks
Looking up Ambush bug it makes a lot more sense then Deadpool/Morph. The art on cards like Retcon, I Can Do That Too, Lemme See That...., and Uh, Yeah, I'm That Guy! fit in a lot with how Ambush Bug is portrayed. Though I like Guise's origin a lot better than the few different ones for Ambush Bug and especially their main nemesis.
The article also seems to confirm that the next expansion released will be the last one.
I know a little bit about Ambush Bug since he showed up in the final episode of Batman: The Brave and the Bold.
What I good show. I really liked Brand and the Bold a lot.
I found that episode and watched it. However, it doesn't really give much of any impression of character really.
On a side note reading the comments was probably a bad idea. I just don't understand the dislike for the art and even the occasional comment to defend it only say it got better with time. My only complaint art wise is just Darken the Skies which has some odd pixelation to to that we've gotten an answer to why it happened. Other then that minor piece I've always enjoyed the art and along with flavor text is my favorite thing about opening new expansions.
I've also never understood the complaints of the art. I mean, I know I dont read many comics from Marvel or DC, but I've seen a lot of art from the web, and Adam's art is good, not "realistic" or "impressionistic" or any other million dollar painting style, but it's good artwork.
And he hasa great ability to imitate many different styles. Think of Mister Fixer’s, Legacy’s, Captain Cosmic’s, and the Enclave’s all next to one another.
Put in a villain, and we don’t have to just think about it.
Art's a very personal thing, and everyone has a different opinion of what they like and what they don't.
And Adam has actually commented that he doesn't like the original art! 
I agree Rabit! Art is very personal.
Everytime you as an artist throw your artwork out there, you're going to get positive and negative feedback from it. All because of whether or not your work fits the viewers taste.
I personally love his style. I actually started practicing drawing humans because of his work. Before getting into this game all I could draw was animals. The Haka fanart piece on the Fanart thread was the first full-human I ever drew. It's thanks to him that I have grown as an artist.
My issue with the comments is more so with just saying it's bad but never really explaining what they don't like about it or what they were expecting from it.
First set art is lower quality.
You can tell Adam didn't have the time, resources, and skill he has now. The volume of art for the initial game, and the fact they weren't a successful game company at the time explains it. Lower volume, better resources leads to better art.
Now I’m trying to think of a villain with a dramatically different art style than the ones I mentioned…
Tempted to say Dreamer or Kismet just for their card backs.
I hope Adam sees this. It would certainly make his day.
There were some issues I had with the art in the original Sentinels, but then I learned that all the art was done by one guy, and I couldn't help but be impressed.
The base set art in particular is very patchy in quality, and unfortunately doesn’t remotely compare to professional comic artwork. Look at something like Shielding Winds or most of Tachyon’s deck, it’s just a scribbly mess.
Sure, you can argue taste is subjective, but you can also analyse general quality, and when Sentinels started in regards to the art you can state that quality wasn’t there compared to the art we get now, or when compared to other comic book based games.
So, while there is a lot I like about it, and I really do love a lot of it, I can definitely understand why people would be put off by it and don’t think it’s something to get annoyed by.
Adam's art has gotten better over time I'll admit. The difference over time being that he has more dedicated time, and tools/equipment. With those he had been able to add in more detail than he could with he original sets. As far as professional comic book art goes Adam's art would fit in easily even the base set.