* Wormwood is not an ingredient in the game. It's a magical herb used in potions, but it's not featured in this particular game.
* The PSP version of *Half-Blood Prince* doesn't include every detail from the book. While it follows the main plot, many minor details, such as specific ingredients for potions, are left out.
If you're looking for wormwood, you might find it in other Harry Potter games like *Harry Potter and the Order of the Phoenix* or *Harry Potter and the Sorcerer's Stone*.