This is lovely! Glad you still pixel! =)
I agree with tanuki about the scrolling speed; also the legs look like he's hopping half steps only (because you duplicated frames, you lazy you).
I love this guy! Great backdrop as well, the overall style is wonderful.
This is really very good, but I have a suggestion for it.
I feel like the speed changes. When the Small Dark Cactus (sdc) is in view but the Large Dark Cactus (ldc) is not, it seems to be at a slower speed because there is nothing in the image moving at the speed of the ldc. It seems like when the Light Cactus (lc) comes into view on the right it hesitates for a moment and then lurches forward. It first comes into view at frame 17 with 2 pixel columns visible. At frame 18 it moves forward only 4 pixels. But when going from frame 20 (the last one) back to frame 1 it moves forward 7 pixels. That's the exact point I feel like it the speed suddenly increases, especially because one frame later the ldc appears in frame 2. The rest of the time the lc moves at a constant speed of 6 pixels per frame, as far as I can tell. The sdc also changes. It's 6 p/f most of the time, but after frame 16 slows to 4 p/f on 17, 18, 19, and then speeds back up to 6 p/f on 20. So that also happens at the same time the lc had its slow down and during all of that the ldc is out of view entirely. The result is that everything in view (I haven't bothered checking the clouds) not only looks like it's slower because there's no fast moving foreground to compare speeds with, but it actually is slower. The ldc seems be 12 p/f the whole time.
My suggestion is to have a very short cactus that we can only see the top of on the same distance layer as the ldc and moving at the same speed, but far enough to the side of it that when the ldc is moving out of view this new cactus will already be back in view on the other side. That way there'll always be a representative of that distance layer, and speed, in view. I also think it would be good to treat all the objects as their own distance layer and have the lc move more like 4 p/f while keeping the sdc at a constant 6 p/f and the lcd at 12 p/f. The clouds could move very slowly at 1-2 p/f (although that would require far more than the 20 frames there currently is).
Overall I think you did a great job.
That video is wonderful, The character is so cute. And I love the retro version of 'the good the bad and the ugly' theme music.
This is excellent! It might add more personality if his arms switch poses every few hops (like forward -> back).