Rawr!

All of them have a bottom-border.

and off topic and i might be crazy, but i personally think it would look better if the line between luigi and mario wasnt so sharp....jus a suggestion

umm yes??
yeah and this was the last one like this dont worry guys.

you've overused the style. The ligthing is pretty awful in my opinion, i know you probably don't want them to be, but the renders in all 3 of them don't suit the flow of the signature. The background is awful as well.
No text is making them look kind of boring.

I like the style if you work on it more, and don't overuse it.

Now to think of a new style, hmmmm.

I've seen the lines in your sigs so much it's boring now.

Yeah, i killed it.

What lines, scan lines?

the diagonal lines

whateva i really dont know anymore

All 3 of of the Nintendo sigs look freakin awesome. Color is really good, it jumps out at you.