I'm imagining a shelf where the main line is presented. This shelf consists of: - Sonic 1 (THE debut) - Sonic 2 (THE legendary sequel) - Sonic 3 (+ a copy of the Hard Times vinyl) - Sonic Spinball - a copy of NiGHTS into Dreams for whatever reason - Sonic Adventure DX: Director's Cut (PC) - Sonic Heroes (NGC - JP box art) - the whole Advance series (also JP box art) - an N-Gage with Sonic N in it - ... The shelf ends here, instead there's a series of posters celebrating the simultaneous release of Sonic games "on all 3 consoles" and a poster of Yakuza 7. The rest must have been stored somewhere on the roof in a box.
I haven't got an exact price, but Chaotix probably sold at retail for $69.99 in the US, as that seems to be standard 32X game pricing. That's $125.38 in today's money.
Since games can be canon without being mainline, I'd personally define mainline games as ones that contribute meaningful additions, changes, or refinements to the game design (while still being platforming-action games) or aesthetics of the series. I'd say this is because Sonic Team is always trying to move Sonic forward and try new ideas, but really, it's so I can omit the 8-bit games (which try to replicate the style of the 16-bit games in a lower fidelity) but include the Advance games (which iterate on the 2D games using the Modern style). So I would include: Sonic 1, 2, 3&K Sonic CD (was spin-off for a while, but has since become mainline) Sonic Adventure Sonic Adventure 2 Sonic Heroes Sonic Advance 1, 2, 3 Sonic 06 Sonic Rush, Rush Adventure (SRA doesn't really add a lot, but it also doesn't do much to warrant being called a spin-off) Sonic & the Secret Rings Sonic Unleashed Sonic Colors Sonic Generations Sonic Lost World Sonic Mania Sonic Forces Sonic Rangers There are some edge cases: Sonic 3D Blast has Sonic Team devs in the credits, and the isometric gameplay was Sega's idea, but the Flicky hunting makes it too much of its own thing. Knuckles Chaotix doesn't even star Sonic, and its big iteration on the formula flopped. Sega doesn't even consider it the canon introduction of the Chaotix anymore. Shadow the Hedgehog, besides the guns, actually offered some refinements to the formula set up in Adventure, but it's officially been labeled a spin-off, so... Sonic Rivals 1&2 were written by Iizuka, and I see aesthetic similarities to Unleashed's 2D sections, but every level is a race. Sonic & the Black Knight may be a sequel to a mainline, but it strives way harder to have a distinct aesthetic. That's to its benefit, though. It's like it knew the sword-play would be weird and decided to own it as its own thing. Sonic 4 is like the 8-bit games or Pocket Adventure, but worse. What it does has been done before and better. The biggest idea it brings to the table is being able to choose the order you play the levels, but Sonic Colors did a more reasonable take on that the same year, and the idea can probably be credited to Mario & Sonic at the Olympic Games anyway. Sonic Runners includes characters like Erazor Djinn, Mephiles, and the Werehog completely stripped of their context, which feels spin-offy. But, it uses the speed, fly, power archetypes from Heroes and the visual style from Lost World. It was developed by Sonic Team. It explains why the Wisps are still around. I can't decide if this meets my criteria. I guess it adapts Sonic gameplay to a mobile format, but then would Sonic Dash count too?
Because I like Zap, and it goes along well with Boom. We need more funny noises for game names. Sonic Snikt and Wolverine, for example (or Wolverine in Sonic Snikt).
Oh boy I can't wait for Sonic Squelch, that's exactly the kind of game name that would get me to buy.
Part of the reason I'd lump in 3D Blast as a mainline entry is just because at the time of its release, it was very clearly positioned as "the next Sonic game" and Sega marketed it directly in comparison to like, Mario 64 or Crash Bandicoot. Knocks against it are that its gameplay is out of step with the rest of the series and that it was developed by a third party (Traveler's Tales), but Sonic Team did a lot of the conception work and I feel like categorizing it differently based on the gameplay is something we can only really do retroactively. Sonic was more of an established series at that point, but it kind of reminds me about a point AVGN made once about Zelda 2 - as the series progressed, it looked more and more like a black sheep within the Zelda series because none of the other games (aside from the terrible CDi ones) adopted its 2D sidescroller style of gameplay, but at the time it came out, there was no standardized "Zelda formula." Zelda 1 was a top-down game, Zelda 2 was a sidescroller. The fact that the rest of the series took after Zelda 1 doesn't delink (ha) Zelda 2 as its direct sequel. I mean it's not a great game overall so if someone leaves it off a list of "mainline Sonic games" I don't feel super compelled to like, defend its honor or anything, especially as this is mostly an academic exercise anyway. As an older fan I guess part of me just finds it interesting to think how games like 3D Blast, or even Shadow and Secret Rings were once loudly and proudly hailed as "the next Sonic game!" by Sega and treated with the same kind of hype (or anti-hype in Shadow's case) a proper new Sonic would be at the time, only to be shunted off to the side in retrospect.
