Selim Palmgren's Mephisto-Walzer is a virtuosic display piece heavily inspired by the Lisztian tradition of diabolic imagery. Its distinctiveness arises from the jagged leaps and relentless, driving rhythmic energy.
At Henle 7 this is a late-advanced work — the technical demands are serious and sustained. The main demands: fast passage work that stays light and even at tempo; sharp dynamic and character contrasts held together in one arc; and octave passages that demand a relaxed wrist to avoid tension.
Beyond that, expect a waltz lilt that needs charm and a flexible left hand.
Achieving the requisite speed while maintaining clean articulation and character in the octave passages is the main hurdle.
Comparable difficulty and character — good candidates for what to learn next.
A level or two down with the same spirit — ideal if this piece is still out of reach.
Where this piece's skills lead: slightly harder works making similar technical demands.
Lesser-known works by the same hand, at a comparable level.
Ein Mephistowalzer (Op.37no.2) is rated Henle level 7 of 9 — late advanced repertoire, roughly ABRSM grade 8 and above. In the RCM system it corresponds to about level 9.
You should be comfortable at Henle level 7 — meaning you can already play level 6–7 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 Ein Mephistowalzer (Op.37no.2) lasts about 5 minutes.
Ein Mephistowalzer (Op.37no.2) 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 Ein Mephistowalzer by Selim Palmgren, Concert Etude by Selim Palmgren, Ballade No.2 by Frédéric Chopin — see the full similar-pieces list on this page.