True i played through a bunch of old pokemon games and the newer pokemon games (omega ruby/alpha sapphire, and ultra sun/moon) that i never got to play.. 知乎，中文互联网高质量的问答社区和创作者聚集的原创内容平台，于 2011 年 1 月正式上线，以「让人们更好的分享知识、经验和见解，找到自己的解答」为品牌使命。知乎凭借认真、专业.
I only know two so far:. Here is a link to almost any textbook's free pdf version.