Critical Limitation: The DS Lite cartridge for LEGO Indiana Jones uses an internal CR1616/CR2032 battery for save data. No SD card, no cloud, no manual backup. When that battery dies (10–15 year lifespan), all saves are lost permanently.
Hard Truth: If you're on original DS Lite hardware with original cart, your save is on borrowed time. Flashcart or 3DS migration is the only reliable preservation.