Artistic Creation

Creating poetry, plays, literature, songs, and the like requires a Perception + Expression roll. Creating something in a physical medium like painting or sculpture requires Perception + Crafts.
Difficulty is based on how intricate the intended goal is. A simple poem is difficulty 4, but a poem that outwardly praises the king while subtly lambasting him would be difficulty 8. If working with a physical medium, difficulty is based on the size and detail of a project. Also, whether the item is purely art or also functional, such as a beautifully crafted sword.
A play or song also needs to be performed. A good (or bad) roll on Perception + Expression can adjust the difficulty of the performance roll, but a true masterpiece shines through even with poor presenters and a true turd of expression stinks even with a masterful presenter.