Multiclass feats allow you to dabble in the class features and powers of another class. You might be a fighter who dips his toe into magery, or a beastmaster who wants a smattering of thief abilities. Each class has a class-specific multiclass feat that gives you access to features from that class.
Class-Specific Feats
There are two restrictions on your choice of a class-specific multiclass feat. First, you can’t take a multiclass feat for your own class. Second, once you take a multiclass feat, you can’t take a class-specific feat for a different class. You can dabble in a second class but not a third.
A character who has taken a class-specific multiclass feat counts as a member of that class for the purpose of meeting prerequisites for taking other feats and qualifying for paragon paths. These feats can qualify you for other feats; for example, a beastmaster who takes Sneak of Shadows can use the thief’s Sneak Attack class feature, which means that he meets the prerequisite for the Backstabber feat.