Bamuseae by Kazue Rockzaemon Isida is a modern experimental piece for piano. It features disjointed melodic lines and unusual harmonic intervals that give it an abstract, intellectual character.
The primary challenge is executing the varied, unpredictable articulations clearly.
Comparable difficulty and character — good candidates for what to learn next.
Bamuseae is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 4.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of Bamuseae lasts about 3 minutes.
Bamuseae is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.
Pieces at a comparable difficulty and character include Caelum Autumn by Kazue Rockzaemon Isida, Caelum Summer by Kazue Rockzaemon Isida, Caelum Winter by Kazue Rockzaemon Isida — see the full similar-pieces list on this page.