In the singleplayer portion of the game there are 11 CloneMasters whom present between 10-15 levels each. At the beginning you will only be able to access the first tutorial CM (DrillDude) and as you solve the puzzles you will unlock the remaining CM's. You are not required to fully complete one CM before training with another CM. There will be an overall increase in difficulty as you progress, although almost every CM will have one or two very hard levels. The final 3 CM's are made exclusively out of very challenging puzzles
The unique features of Clones (4 gravities, spin and atomize morphs, new game modes) should provide fresh mind-bending situations for those already familiar with the Lemmings-style of gameplay.