When you’re first starting the game, the best thing to do is to get familiar with the basics. Don’t worry about grinding or trying to pick up consecutive flowers, just get a feel for how to move around and not shoot yourself.
While you don’t need the key until you’ve collected all of the flowers, it’s a good idea to pick it up immediately when a stage starts. The key acts as a shield and can protect you from attacks from the rear.
Until you get used to charge attacks, there’s no benefit to getting up close and personal with creatures. Pick them off from afar whenever you can.
Watch out for creatures that are spawning in. If you are unfortunate enough to pass over the spot they’re generated in at the wrong moment, you will be instantly killed.
Fruits are great for extra points, but if you’re looking to stay alive, pay careful attention to any potions the creatures may drop. They’ll do useful things like restore your health or power up your weapon.
Avoid wrap-around hallways and warp tunnels until you get the key. You’ll only end up hurting yourself when your shots loop around.
If an enemy starts blinking red, get away from them. They’re going to explode, taking out chunks of the maze and dealing heavy damage to you if you’re near.
Don’t take too long to finish a level. An extremely powerful ghost will appear after a while and defeat you if you don’t get a move on.