The Lion & Unicorn Shield is treasure that can be obtained in Sly Cooper: Age of Thieves that is found in the episode Alice in Cooperland. It is worth 233 coins and the allotted time needed to get to the safehouse is twenty seconds.
"This shield has been in the Cooper family since the days of Sir Galleth Cooper. The green lion and lavender unicorn seem like perfect opposites, and yet they seem so similar. Lewis Carroll is said to have been inspired by this shield when he made the Lion and Unicorn characters."
It is located in an alleyway outside the safehouse. Penelope is the only character capable of reaching this treasure.