SR388 is riddled with hidden passages and secret rooms, many of which contain valuable power-ups or shortcuts. The game encourages thorough exploration and experimentation.

Tips for Finding Secrets:
- Shoot Everything: Many blocks are destructible. If a wall or floor looks suspicious, shoot it with your Arm Cannon.
- Bomb Everything: In Morph Ball form, drop bombs on suspicious floors or walls. This can reveal hidden passages or break through Bomb Blocks.
- Look for Discoloration: Sometimes, destructible blocks have a slightly different shade or texture.
- Try Rolling: Small gaps that seem impassable might be accessible in Morph Ball form.
- Use the Screw Attack: Once acquired, the Screw Attack can destroy certain blocks simply by touching them while spinning.
Don't be afraid to backtrack with new abilities. Many secrets are only accessible after acquiring specific upgrades like the Spider Ball, Spring Ball, or Space Jump.