Em I do not know anything of the Touhou thing. I think I shall research it up.
^_^ I was just wanting to actually do a review on wat the mod is like etc. And yes an In depth history and wat not would be great on the mod
Thanks
Ult1mara
Hahaha well looks like it's time for me to introduce you to one of the biggest known Japanese doujin game series in Japan.
The very reason I want you to get the idea of what Touhou is, is because you need to have a strong understanding behind the concept of this mod. Otherwise, it probably wouldn't look much different Mike Mayday's DF mod. (which is where the mod orginated from, since it uses some of the same art and stuff from it.)
Anyways, let me give you a few links to start looking around into the world that is Touhou and give you a quick intro to it:
http://en.touhouwiki.net/wiki/Touhou_Wiki - The Offical Touhou Wiki
http://tvtropes.org/pmwiki/pmwiki.php/Main/Touhou Touhou on TV tropes, with some info on charaters, games and plenty of crossovers (including mine is mentioned there)
Brief Summary: Touhou is a doujin game series that is made by a single man known as "ZUN". The game series orgially started back in
1997 when he created High Responsive to Prayer, in which introduced us to Reimu Hakurei. The first game was pretty much an Arkanoid clone with some intense bullet action around boss battles. After that game, ZUN would start turning the Touhou games into more of a overhead vertical shooter series which would pretty make the series what it is today. Course man people reffer to it as a "Curtain Shooter" (or Bullet Hell) because of the large amount of bullets you have to dodge while fighting off eneimes and bosses.
The first 5 games were released on the PC-98. And then after that, ZUN moved to the PC and start remaking Touhou on that system. This is when he took the main charaters from the PC-98 (Reimu and Marisa) and remade them along with Gensokyo in general (though he says that this is the same Gensokyo)
The first PC game was Embodiment of the Scarlet Devil: The 6th game in the Touhou series. And with every year, ZUN would keep release a game that would continue to introduce the world of Touhou to the players as well as new engines, concept, and charaters that would shape the world to it's fans and release tons of doujin in the process.
Overall, ZUN has released nearly 20 games in the series (The 13th offical game in the seires: Ten Desires will be the 20th when it's released later this year). 13 of them which different games that introduce us to new characters and continue to show the world of Gensokyo to the people. Which were almost all curtain shooters.
While the remaining 7 were side story that mainly just took place between the offical games that ZUN lend a hand in making. They were either fighting games, or gimmick based games like Shoot the bullet. (Think Pokemon Snap, but while dodging bullets)
Course ZUN also did some other side stories in the form of manga and novels. Which introduced even more stories and charaters to the series.
About the World of Touhou: Touhou takes place in a mythical land known as Gensokyo. A land that is supposedly located somewhere in Japan and is hidden away from the Outside World back several centeries ago to remain hidden from being exposed to the ever growing development of technology.
Inside the world of Gensokyo, magic exsist as well as many mythical creatures from fantasy and Japanese fokelore such as youkai, Kappas, Tengu, faries, ect. Because of the fact Gensokyo is hidden away from the outside world, everything in there is still as if it within 19th Century Japan over there. Course even barrier aren't always perfer, as some things do come in. And at times incidents occur, which is when the Shrine Maiden, Reimu Hakurei comes into to action along with the Magician Marisa Kirisame as they are the two the mainly get invovled the most to try to investigate the cause of the incidents and resolve them.
There are way too many to talk about here which is why I'm giving you the wiki and tvtropes to look over. If you do become more interested I can give you some other stuff to look over. Doujins, artsite, ect. It shows a great deal behind what Touhou has become.
What about Suika since she's part of this DF mod?Well that's part's easy to explain. In the game Immateral and Missing Power (Touhou 7.5) we get introduced to an oni named Suika Ibuki (Who's the final boss in that game). She's this little drunk oni who is known for her power to manipulate density. She uses it to make the people of Gensokyo gather and party non-stop (she was trying to get oni to come back from the underground since they went into hiding down there). But her density control doesn't just work on events and peole, but also the mass of thing. Including herself. As she can make herself gigantic in size. Or as in other cases pluck out some hair and make tiny duplicates of herself.
Because of the fact she makes tiny copies of herself that how I got the idea behind this game. Cause I wanted to use a Tohuou charaters in large numbers, lives underground (Onis do that in the touhou series from what I gathered) and need beer to get through the working day(which she always loves to drink and also throw lots of parties.

) Thus she was perfect candidate to replace the Dwarf.
And as the fanbase says: If there's a game out there, Touhou will parody it one way or another.
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But yeah this is just the tip of the iceburg here. I you should try to look through the Touhou Wiki and Tvtropes, heck, go play a game, get the feel of it if you like. ^^ (or youtube up gameplay footage)
I will send you a PM later with my history behind the mod and how everything came up to where it is today.