All Weapons and Health Refill
At the title screen, press Left, Right, Up, Down on the control pad. Then hold the Z button and press Right, Right, Left, Left, on the control pad. You should hear a confirmation sound. To use it, press A + B + R while playing the game to refill your life and give you all of the weapons. submitted by J.J. Hale

Dark Stinger
To play as dark stinger perform the following:

As the game is loading hold Z and UP on the joystick. Then press C-Up, C-Right, C-Down, C-Left 5 times. Next press B, A, B you should hear a confirmation noise if done correctly.

Defeating the Queen
To really let her have it, shoot her in the HEAD with the manually guided missiles (the one to the left of the big shoulder cannon when you select your weapon).

To kill her in phase 2 (the caterpillar) turn to face her and then shoot a manually guided missile at her head and then once you know its aimed properly don't wait for it to hit her, shoot another one and aim it again. Repeat this process until she is dead.

Note: If you get hit while maneuvering a guided missle you will lose control of it and you will have to try again.

This tip is most effective when you activate the 'All Weapons and Health Refill' code. Keep refilling your life and weapons to make sure that you don't run out of ammo and die. submitted by Syruns Jeanes

Easier Time Destroying Enemies
Instead of using the normal laser beam as your primary weapon, try using the Plasma Cannon. (The weapon you get from the bees) as your primary weapon. This way, most basic enemys will fall down with just one shot of the gun! submitted by Rediga Yoshi

Easy Way to Destroy Bees
Here is an easy way to destroy bees: Wait to hear the buzzing sound that notifies you of their arrival. Then wait for them to get very, very close to you (when they lower their altitude to hit you). Use your weapon with star-type ammo to shoot them. You will hit them 99.9% of the time. If you shoot them and they hit you, you will not lose as much health as normal. submitted by Jon Roe

Fast Forward Text
When text appears press Z to fast-forward or A to skip it entirely. submitted by Josh (jbillos@icok.net)

Level Select
On the title screen, hold the Z button and press Right, Down, Down, Right on the control pad. Then release Z and press Right, Up, Down, Left, Left, Up, Right, Right. You will then here a tone and when you start your game it will ask you to select a stage. submitted by Weebit

Special Gun
On mission 6 there is a special gun you can get. First pick up the nuclear device and then while carying the device fly up towards the mountains to a steel like drum. Fly over the drum and a special gun will appear and some ammo with it! submitted by Steven Yearwood