Super Mario 3D CAT

[E-Man]

While the park might have some Sonic influence (it's possible), it also fits in with things Bowser has done in the past. Such as his clown car or, if we can dance back to 2002 for a bit, Mecha-Bowser.

Speaking of which, even though Bowser did those things before Sega and Nintendo had a "truce" of sorts, they all seem like things Dr. Eggman would have done himself. The Clown Car is almost identical in function to the Eggmobile, while a giant robot in his likeness has been done more than once by Eggman.

Sure, these are all coincidences and Bowser needs to grow a mustache and gain a high IQ (bragging about having an IQ of 4,500 in that one mediocre Mario Party game doesn't count) before he could be close to copying Eggman, but it almost seems like Nintendo borrowed some ideas from Sega (well, almost anyway).