where to start?...the animation was great, the voices were great, the flash was funny- all in all it's a great flash.
I like how you chose this is ness vs sonic( you usually see sonic vs shadow or mario).
I dont play any games with ness in it except for super smash bros so i wouldnt know what kinda moves he really has (like if he has PK rocket or not) so im gunna guess that you made some moves up too, and some of the moves(if im right and you did make them) are quite funny, creative, etc. (good job)
There are aLOT of other thing you did well with this too, unfortunately there are only 4000 characters remaining in this post and trust me i could NOT go through all the things you did well on this with only 4000!
The only thing i reccomend you do with this is( I know that you have this on youtube, but this is a suggestion for you for the NG users sence you cant pause on NG) try and make the in-circus scene alittle slower, i couldnt tell who all the characters were who were running around w/DK, Ness, and Sonic.
Oh that reminds me even though this is a Ness VS Sonic Flash i thought that was a REALLY cool idea putting other Nintendo characters in also- like DK, Pikachu, and Kirby!
all-in-all 10/10 and Im looking forward to your next submission!