I'm sure that you've heard of Touhou Puppet Play (referred to as "Touhoumon" from this point on) at least once by now, and that's what this is. For those of you innocent enough to not know what it is, it is a Japanese fakemon hack of Pokemon Fire Red that replaces Pokemon with characters from the Touhou Project series while still following the basic progression of Fire Red. The latest version, 1.8, was another huge shift which was more focused on balancing the power creep between obtainable characters along with a new type chart and the Physical/Special class split for moves.
There are two main features to 1.8. The first main feature is that stats are very balanced and nearly everything (barring a few joke characters) is viable without abusing X Items or overleveling, and the second is that the vast majority of the cast has multiple evolutionary paths they can take by either leveling or simply using an evolutionary stone. As an example, something's level evolution could be a slow bulky special attacker, but by using a stone it could choose to become a fast physical attacker instead. This allows for a large amount of variety in team building, and adds replay value.
Now that the boring preface is out of the way, let's get to the main draw here: this is a hack of Pokemon Emerald (U) that uses Touhoumon's lineup of obtainable 'mons to take everything you know about Pokemon and snap it in half. This hack follows Hoenn's basic plotline and gameplay progression, but the changes to the 'mon lineup, attacks, and type chart changes the game rather drastically. Its mostly vanilla Hoenn since that was my aim, but there's a few curve balls thrown at you to keep you on your toes.
Anyway, now for some screenshots that I hope will show there's been enough changes to the ROM for this to be worth posting:
"But wait!" somebody cuts in, "Can I still enjoy this if I don't know the first thing about Touhou?"
Well, yeah. It's still just Pokemon. A lot of the typings will make more sense if you know the characters, but there's a fair amount of documentation about 1.8 to tell you what character/move typings are.
"I don't want to learn a new type chart. That sounds dumb."
You learned a type chart when you first played Pokemon, didn't you? Just leave a type chart image up, it's not hard.
"I played a Touhou hack before, and it was an obnoxious grindfest where things just had high stats. Is this hack like that?"
No, because I'm not a complete idiot. That said, the difficulty level is overall higher than vanilla Emerald, but you won't have to grind to 100 or anything for the main game.
"I've seen Emerald hacks that replaced Pokemon before, and the Battle Tents and Frontier were a complete mess."
Not this one! The Battle Tents and Battle Frontier have been edited to reflect the in-game changes. They're fully playable, and they will kick your butt up and down the street if you're not careful.
Okay, here's some screenshots of a few of a few things in the Frontier list, taken from the Battle Factory:
Now that that's out of the way, the hack can be found on this page.
I host download links on an external web page so I don't have to worry about updating download links every place I post this, so I hope you understand. Along with the patches, I've enclosed just about every resource you could ever need for hunting items, knowing the level curve, so on and so forth.
As for a credits/thanks list:
Nintendo/Gamefreak: For Pokemon itself
ZUN: The guy who came up with Touhou Project and its characters, any Touhou content is his own creation
HemoglobinA1C: The man who made the sprites for the Japanese hack. He's stated that his sprites are all free to use as long as he is credited, and this is where he's being credited (outside of the readme file, of course)
Darthatron for the old Physical/Special split used for quite a while
DoesntKnowHowToPlay and Tailes of the Nuzlocke Forums for the current Physical/Special split
HackMew cuz look at all these crazy solid tools
Scizz, Silver314, Wichu, LU-HO, thethethe, and many others I may have forgotten for tools they've created as well
Chrisitan Mass for the hex editor XVI32
Bulbapedia for having Frontier structures well-documented