Tutorial
I have no opinions on this except it does a decent enough job of explaining the controls for this game I guess.
Greenflower
An excellent introduction into an already pretty good game. Its playground-esque design gives plenty of opportunities to let the player mess around with the controls and get into the feel of gameplay. I especially like how the 2nd act opens up and gives the player a sense of speed and freedom.
Techno Hill
I have nothing bad to say about this. Open, freeflowing, good gimmicks, multiple pathways, secrets high and low, impressive sense of scale in the second act, what more needs to be said?
Deep Sea
Similarly fantastic, there's so many ways you could go in this stage and while they all lead to the same goal, each path feels fresh and exploratory, interconnects with one another at times, and is still freeflowing and good.
The only problem I have with it is that some areas need more bubbles and that's about it.
Castle Eggman
If you're a newcomer, this level is a bitch-slap and a half. This level harbors a deceptively high difficulty spike. There's spikes everywhere, bottomless pits, and sudden precision platforming. If this game wants a better difficulty curve, this level NEEDS to be nerfed in terms of difficulty; Spikes need to be toned down, or moved to better positions, and the platforming and enemy placement similarly needs to be nerfed. The bridge at the end of act 1 is a good example of this, every newcomer dies repeatedly to this section, and it's hard to not notice why, the spike placement is especially bad in this part, I've seen this part being compared, level-design wise, to Sonic World (the fangame that's infamous for its level design randomly plastering hazards everywhere, hmmmmmmmmmmm)
Otherwise, if you're a pro, this level is really good. It's sense of scale, verticality, and openness is extremely impressive and nice. I especially love flinging myself around in act 1. The amount of alternative paths (mostly in act 2) is astounding; I can never get old of this level, it's clearly one of 2.2's best, despite its performance issues.
Arid Canyon
This one, in terms of difficulty, is a nearly perfect mid-point, where things get hectic, but not too dangerous...........yet. It continues 2.2s trend of making vast, open levels with tons of alternative paths, secrets, and freeflowing level design. I especially like how, in act 1, a lot of the pathways loop back in to a central area, making you truly feel like you're traversing a tall canyon. The minecarts in act 2 are especially a nice change of pace, giving the level a bit of variety without going too overboard and gimmick with its uhhhhhhhh gimmicks.
My only complaint is that the badniks are kind of annoying to hit/dodge, otherwise, great level.
Red Volcano
This level is already a huge step up from the previous version, especially since the platforms were made bigger, the level more open, and the difficulty less awkward and jank. I especially like how each of the do-or-die sections were given alternative paths. However, the level still needs refinement.
I'm quite leery about the rings dissipating in lava, I can understand this to be an anti-cheese mechanic, but then again, people will come play this expecting classic sonic gimmicks/quirks from the get-go, and seeing the rings disappear like that when they didn't do that in the classics is uhhhhhhhhhhhh weird.
The enemies are mostly good, except the pterodactyl. It's zero-threshold dive comes out of nowhere, with the only indication being the SCREEEEE and the fact that they hover around perilous places beforehand. You can mash jump to escape their grasp and steer yourself back to safety, but there isn't any good indication that you could do that, leading to newcomers getting grabbed and then getting dropped into the f i r e w a t e r to kiss their rings goodbye. Speaking of newcomers, this level also represents a large difficulty spike, nerfing the difficulty on this level by a medium-small bit would definitely help, especially once the two remaining zones gets put in to fill the challenge quota this campaign needs.
Egg Rock
It's outdated, I know, but I'm gonna bitch about it regardless >:^( Every single gimmick, hazard, and idea this stage introduces each has potential, the problem is, none of that potential is fleshed out. Every single hazard, gimmick, and idea is woefully undercooked. No challenge introduces itself properly, so the player gets confused and dies. No gimmick fleshes itself out, so the player gets underwhelmed and dies. No idea is given the proper screentime, so the player forgets about it and dies. Now that I think about it, the player dies here alot, don't they. The obnoxious difficulty spike doesn't help either. I like it in a masochistic sense, but its clear that this level needs to be remade. As, in its current state, feels like a bunch of concept maps strung together haphazardly to make a "level"
Metal Sonic
I actually really like this boss fight. The race does a decent enough job of being this final bastion of pure skill and difficulty, but leaves a lot to be desired. The actual boss fight, while still better than its incarnation in 2.1, still needs to be refined. The part where you have to get close to it feels incredibly awkward, especially close to the edges of the arena, I prefer there be a different way to expose the boss other than to invade its personal space.
Brak Eggman
To defeat
the cybereggman
hit it
until it dies
But first, you have to lure it into some toxic goo, which never felt right and always killed the pace of the boss fight. Maybe make it vulnerable all the time, give it more hit points, as well as edit the arena to include many line-of-sight breaks, and maybe, just maybe, we could have a REAL cybereggman boss fight. DOOM-style~