Hints and Tips

You have infinite lives to clear the level. So don’t give up. You’ll get it eventually.
The flashing red and yellow squares are Shields. You are (relatively) safe when standing on them.
Learn how the enemies move. It helps you avoid their attacks if you know they pass through walls.
Be sure that you write down the password for each level. You never know what might happen.
The last few levels before Chaos Gear are easy if you take your time. If you try to rush through things, you’ll make things impossibly hard.
Hal Tosa shoots directly at you. You’re a sitting duck if you stand still.