I know about the "special" Katakana that are [typically taught](http://www.guidetojapanese.org/learn/grammar/katakana), like ファ *fa*, ディ *di*, etc.  However, I keep running into others that aren't found on any Katakana lists I've ever seen, including the one in [this question](http://japanese.stackexchange.com/questions/15119/what-special-kana-are-used-to-write-foreign-words).

For example, on [this wikipedia page](https://en.wikipedia.org/wiki/Zero_Escape:_Virtue%27s_Last_Reward), one of the character's name is listed as:

> **Quark** (クォーク Kuōku)

I asked my friend who is fluent in Japanese why "kuo" is written クォ and not クオ, and he said *"The correct romanization for クォ is kwo."*  I've never seen クォ in any Katakana list.

Another example I haven't seen anywhere is フュ *fyu*, seen in the new movie [X-MEN: フューチャー&パスト](https://ja.wikipedia.org/wiki/X-MEN:_%E3%83%95%E3%83%A5%E3%83%BC%E3%83%81%E3%83%A3%E3%83%BC%26%E3%83%91%E3%82%B9%E3%83%88).

So, **is there a *complete* list of Katakana somewhere online?**