The best puzzle games are a slow, teasing exercise. You build and you build and you build, and then eventually you can't stop it any longer - the screen fills up, the time runs down, and you feel like you can't go again for another half an hour. Sometimes you punch through your high score and it all seems worth it. Sometimes you stare at your stylus or d-pad in disbelief.
The idea is to move a little man/dragon/other around 185 small grid-based levels collecting all the gems so that you can walk into a box at the end and move onto the next. To gather them all, you'll have to work out how to make use of all the available crates to bridge water or lava, take advantage of or avoid speed-up and slow-down icons, dodge, disable or destroy enemies with recognisable movement patterns, and gradually build up to applying all these skills and other similar ones in concert.
Following a quick and dirty introduction across 'Tutorialand's opening 15 levels, and with per-level tips for getting used to new objects and techniques, Frantix becomes a case of applying the logic to whatever you face in an increasingly complex manner. Where previously you might have had to fence in a catdragon so it dies in the sand before pushing a bomb up to the other end of a narrow pathway to blow up another one, a few levels later you may have to carefully consider the order in which to dunk blocks in a stream to create a bridge, and how to get them into the right position without rendering the rest of the level impossible.