The Enderman
The Enderman will pick up blocks and move them. If you hit them or look them in the eyes then they will go to attack you. They also have the ability to teleport. This mob will drop Ender Pearls. You can use Ender Pearls to craft Ender Eyes which can then be used to access The End.
The Wolf
The Wolf is a wolf and can be tamed as a pet using bones. if you hit a wild wolf it will look mad (Bottom) but if you tame it, it will get a collar (Top)