描画や着色用の粗いエッジのマーカー。 marker with rough edges for rendering/coloring.
厳密には混色・ブレンドブラシではありませんが、色を組み合わせたり、色を一つにまとめたりするときに不透明度や圧力がとても良く、色がすごく濁ってしまわないときにとても効果的です。
より明確な状況――>

not technically a mixing/blending brush, but the opacity/pressure makes it work really well if you're combining colors or working a lot of different colors into one piece, but don't want them to become super muddy.
clearer picture -->
