At the suggestion of Jebby, Krotomo, and Shos I'm going to facilitate the creation of a new tutorial/campaign for HATPC Reborn which introduces more mechanics and introduces them more gradually than the original. As the first step in that, I'm throwing together a list of topics that this new "tutorial" should introduce. At the moment, they are in no particular order. Well, they're roughly in the order they might be introduced in, but we can work on ordering them once we've figured out what exactly goes on the list. I want this list to be as specific as possible, so feel free to suggest anything that can be added two it.

I've grouped them roughly by type. Basics have to be introduced in the first level, or at least before we get too far into other mechanics. Blocks is simply a list of the different block types to be introduced (Note that secret area and gem crates are not to be introduced explicitly - I want the player to organically discover them like in the original). And extras is a list of mechanics above and beyond the basic block types to be introduced. That last section will probably be expanded greatly as you guys suggest things to add to it.

So what are you waiting for? Get suggesting!

Running through the list of tricks and glitches on http://www.interguild.org/blogs/?id=5232:

Removed in (or not planned for) HATPC Reborn:
    Air refill through ladders
    Disappearing arrows
    Disappearing dynamite
    Duckswimming (I plan to use the ducking hitbox for all swimming)
    Dynamite going through terrain
    Dynamite skipping corners
    Fast swimming (Swim speed will always be the same)
    Getting stuck in corners
    Getting stuck in objects underwater
    Jumping through arrows and dynamite
    Jumping through corners underwater
    Jumping through corners with ladders
    Jumping through corners with platforms
    Jumping through diagonally touching spikes
    Monsters falling through solid objects
    Monsters walking through solid objects
    Objects falling through the floor
    Object respawning
    Retaining momentum when breaking through wooden crates
    The Great Glitch of '07
    The Great Glitch of '08
    Shockwave Error
    Water Drain (Although I might add a tile that does that.)
    Water taps going through walls
    Water rising through terrain
    Zero G

Already on the list:
    Duckjumping

What even is this:
    Duckclimbing
    Jumping ontop of a falling crate at 4 tiles high
    Jumping out of a crawl space as a crate is falling in front of it
    Jumping over spikes 4 tiles high
    Jumping through spikes at a corner
    Near Zero G
    Phantom Crates
    Rolling multiple boulders at the same time
    Stopping arrows and dynamite with boulders
    Turning boulders around

Not relevant for the tutorial:
    'Error; you are stupid'
    Floorless/Wallless/Ceilingless Caves
    Getting stuck in objects through invincibility
    Multiple hearts and gems
    Multiple doors
    Removing rows from your cave
    Standing on the edge of spikes
    Untitled Caves
    Uploader character limits

Things to discuss:

    Fake tiles - I'm not sure I want to implement these at all. They seems antithetical to the spirit of HATPC - that is, the spirit of transparency. Generally in HATPC you can see what's going on so you never feel cheated when you fail - you feel like it was your fault. A tile that appears to be something it's not violates that spirit.

    Getting stuck in objects through platforms - This is mostly removed in HATPC Reborn with the exception of with boulders, but jumping into boulders with platforms is worth including in a tutorial.

    Jumping between arrows - As-is this is not really a thing in HATPC Reborn - in 0.2.6 I just removed the ability to fit between vertical arrows, and while you could theoretically duck-jump through horizontal arrows I think in practice you don't hang in place for long enough. I might re-introduce jumping through vertical arrows though.

    Objects falling through arrows - Totally a thing. IDK if it's worth a spot in the tutorial though. I suppose it can be introduced in  practice without being explicitly explained.

    Pausing by right-clicking - Not a thing currently, but you can pause by pressing K. That might be worth introducing in the tutorial.

    Starting invincibility - Probably doesn't need to be explicitly explained.

    Swimming between arrows - Will probably be a thing. I'll add it to the list.

Any particular reason Zero G is being left out of HATPC Reborn? It's pretty difficult to use it in a cave unless you center the level around said glitch, but it's definitely one of the weirder quirks.

Also this might not be the same for everyone, but I would say I predominantly did not use fake crates to trick the player. I barely used them to begin with, but they're useful in ultra specific situations where you need a row of *insert tile here* to suddenly stop existing, but it may not be feasible to destroy said row by traditional things such as dynamite/arrows/boulders. As I said, it's highly specific, so in the event such an option was removed, I guess people would naturally figure out different solutions to such scenarios

Fake crates and zero g are glitches would have to be specifically coded in, so I think don't bother. I'd expect the game to have its own complement of glitches...

Duckclimbing - Like duck-swimming but for ladders.

Jumping onto falling crates - You can climb a stack of metal crates as they fall by landing on one, jumping out of the way and landing on the next one, ect. Without any extra help, the highest stack of falling crates you could get on top of was 6 tiles high.

Jumping out of a crawl space as a crate is falling in front of it - Uhhh... I'm gonna guess you can jump out at the same time as the crate lands and not die? I've never used this trick.

Jumping over spikes 4 tiles high - ummmmm

Jumping through spikes at a corner - Lots of jumping through spikes tricks. The terrain push thing can get you past spikes. And spikes at a diagonal you can get between...

Near Zero G - If zero g is done, then so is this. Weird stuff can happen if most of the slots for falling objects are full. You can duplicate crates with it too.

Phantom Crates - fake crates maybe???

Rolling multiple boulders at the same time - If a boulder lands on another boulder and you move the bottom boulder, you can essentially push two boulders at once. Boulders themselves can do this without hannah pushing the bottom one, but they have to both move on the same frame or it doesn't work.

Stopping arrows and dynamite with boulders - Uh... I'd guess this is the thing where you can have a boulder survive if you push it right after it gets hit.

Turning boulders around - If a boulder lands next to a wall, if you move into it as it lands at just the right time, you can it to dislodge from the wall.

I'll be a little more explanatory than csd:
when you try to enter crawl spaces, you have to be ducking (unless water..) so if you duckjump into a ladder and hold UP AND DOWN, then you don't move (you can still move up with jumping) and you'll be able to get into crawlspaces.

Jumping out... yeah. if normally a metal crate would block your way, well, if you jump in the split second before it lands, you can jump through it.

4 tiles spikes - it's just super hard and like 1-pixel accuracy.

Near Zero G is just way beyond anyone, lol.

Really awesome to see this being planned out.

One request though. I’d rather the tutorial didn't have dry names like “Tutorial 4: Boulders”. They should be “organic” community levels that also happen to have teaching the mechanics in mind. Even if it's just through giving them creative names. It should feel like a real set of campaign levels - maybe have that in mind when building these levels. A good platform campaign shouldn't need explicit tutorial levels - it should teach the mechanics along the journey, almost as a by-product. I personally get turned off when I see I have to go through 10 "tutorial missions" before I can get to the juicy stuff - if it seems like a real campaign from the beginning, all the better.

So, for example, rather than "Tutorial One: Moving", it could be "Hannah" or "The Journey Begins" or something vaguely creative.

Once all the basic mechanics have been covered, it shouldn't stop there. There should be some more creative levels that gently crank up the difficulty while combining the mechanics that have just been taught in interesting ways. A simple example is a trailblazer style speed cave. You aren't learning about any new tiles or moves in such a level, but you are learning about how they can be combined to create a level that forces you to constantly be on the move.

The Interguild community enjoys making devilishly difficult puzzles through what I call combination locks: "to unlock a new area/treasure/door, manipulate these crates in a specific order, one that may require other combination locks to have already been completed". These can be introduced into the campaign levels, slowly escalating in difficulty. We want people to at least have the common HATPC tropes (?) in their head before being let into the Wild West of user levels.

hmm. You still do support some tutorial messages though, right?

Absolutely. In fact, I support two methods of creating tutorial messages. The legacy method from HATPC (level name beginning with "tutorial", numbers 0-9 in the level code, messages on lines starting with ?) and a method using the new event syntax (same as checkpoints). To learn how to use the new syntax, see this guide: http://www.interguild.org/blogs/?id=69411