the game should save your progress after each completed level. As long as you don't die - you can switch off the GBC and return to your current level. If you die though... it's tough nuts!!
OK - saving after a level is (now) not a feature of the GBC. You gotta go big, or go home!!!
We deliberated a LOT over game saves, but in the end we have to stay true to the game's roots.
