Oh No! More Lemmings (ONML for short) is a computer game expansion to the Psygnosis game Lemmings. Sometimes referred to as the "data disk", it contains 100 unique single-player levels and six new music tracks. The Amiga version also includes 10 two-player levels. This game is not the official sequel to Lemmings, a title that goes to Lemmings 2: The Tribes.
The game requires either the install disk from the previous Lemmings, or, in a standalone version, the game manual, for use as a copy protector. The new levels are separated into five difficulty categories (Tame, Crazy, Wild, Wicked, and Havoc), each with 20 levels.