This is one of my favorite patterns. The purple one is arguably my favorite amigurumi project. The orange one I just finished for someone else. I love to see the difference in hook size and yarn type when using the same pattern. the Orange hippo is made out of red heart soft and purple is sock yarn.
Pattern is Lion Brand from: http://www.amazon.com/Vannas-Choice-Crochet-Critters-Leisure/dp/1601404956