Shape Shifters differ from Werewolves in that they transform at will. Most shape shifters have their normal intelligence and total control over their actions while in their animal form, another difference from werewolves.
A witchen shape-shifter can become any animal developed by mother nature, as long as they have former it within their power. Or, they can shape shift into an actual mysthical creature, as long as it is for real, and not made up.
A limited shape shifter turns into only one thing. The most common animals that shape shifters (shiftling,changer,etc.) turn into are wolf, bear, minotaur, cat and lion.