Sonic Forces

First, let's say that the robots are very similar to the Death Egg Robot however I do NOT think that they are being controlled by Eggman, Instead, I believe that they are being controlled by a bigger threat, such as the Deadly Six, but it's unlikely.

After that, we see Sonic spinning right onto the ground - oh, I should mention that I don't think that was the Drop Dash, because I have a better thing for that ability. Get this. After Sonic Generations, a new timeline was created, and 2 started to exist in the same universe. One, where Sonic didn't meet with his older self in the past, and went through the 3D era normally while becoming FAST. Another one, where Classic Sonic saw his older self, and started practicing to become as good as he is. He never went through the 3D era (and as such only met Tails, Knuckles, Fang and Amy, which never went thourgh her modern change) and instead mastered 2D platforming and skills, and became extremely VERSATILE. That's the Sonic Mania timeline. It's also where Knuckles teams up with fang to be tricksters, and not becomes a dumb fella with no sense of adventure and conical depression. lol.

The 2D part of the teaser showcasing Modern Sonic has led me to think of some possibilities for his gameplay:

1. Modern Sonic will have 2D sections and will be able to switch between lanes, maybe with his Quick Step, or by the use of springs (similiar to how Kirby uses a warp star to switch lanes in his games).

2. He'll only have 3D sections, but the 2D perspective was a hint at Classic Sonic's appearance.

3. It's a preview of Classic Sonic's gameplay: he was able to master 2D platforming, so he's able to switch lanes at will, using the background as his advantage. I think this is the one that makes the most sense, since it follows my theory the best.

Next, therer's Classic Sonic boosting. Well, following my theory, I'd say he was able to master his Peel-Out technique in a way that he can activate it while walking, hinted at by the sound made, similar to that of the Peel-Out charge in Sonic CD.

Now, the phrase Join the Resistance has led to many speculation, but I think it means something else. Union. The resistance is the union of all. Good and evil. Past, and future. Exactly what the Sonic Mania trailer said.
Boom Sonic fits in this, obviously. And while people wouldn't like to see him in a game, I'll just break it up: Sonic Team is best team. They wouldn't be so stupid as to put him there for no reason. Boom is coming back, to fit as the one from another universe, who's there to help save the world from the threat which could potentially wipe his world out. Oh, His World. Reminds me of '06. And past and future do too. Shadow and Silver... Iblis. The teaser showed fire, Iblis showed fire. Maybe Iblis is back. Maybe the Time Eater brought him back. Whew, this is getting nice...

Now, it's the union of good and evil, too. Think about it. If there's a bigger threat, even Eggman would chicken out of the base and join the blue hedgehog's team. Maybe he and Tails could team up to create machinery for detecting safe territory, and protecting it. Teaming up reminds me of Heroes. Oh, yeah. Remember the teaser spoiler? Those words I capslocked... FAST and VERSATILE define Modern and Classic Sonic. The word that defines Boom is STRONG, because of his combat experience. Speed, Fly, Power. Yeah, C-Sonic can't fly, but it fits, doesn't it? The one and only, the TRUE TEAM SONIC.

*snip*