This Spellarium installment is pretty tough in spots, while other levels are walk in the park easy. There are 110 M3-puzzle levels and probably at least half that many minigames total (HOS, spot the difference, mahjong, solitaire). With the difficulty being all over the place, there's no telling when you'll get a level which can be rendered impossible...
Its one of those -just one more level games. Where, if you are not careful, you can lose hours playing it.
The following oft repeated hint from the games sums things up nicely:
"Follow the right sequence or it will take too long to complete this level!"
First off the bat - it simply isn't true (in casual mode there is no timer and no move limits; although this can be changed if you want more of a challenge). And some of the other instructions were oddly...
