Checkpoints are critical finds in the labyrinth. If the worst should happen and Murkon dies, then some careful manipulation of the space-time continuum will be performed, and time will be rewound to when you reached the last checkpoint. Anything done since reaching that checkpoint will be undone, and you'll have to replay the game up to where you died, or take another course of play altogether. Checkpoints are usually plentiful in the labyrinth, so usually you won't have to redo very much of the game when you die. Note, however, that checkpoints disappear after you reach it, so you can't hit it once to save your progress, then go make some more progress, and come back to the same one to save again. Therefore, in areas with multiple checkpoints, do NOT hit them all at once. Instead, space out your usage of them, so that you can consume checkpoints periodically as you play. Also, an important side effect of hitting a checkpoint is that any partially wounded parties of characters will get a chance to heal. This may or may not be desirable, depending on the situation; use your own judgment about whether to hit a checkpoint if there's a partially wounded party out there from a previous battle.