You will have a choice of eight different boss areas. Choose Galaxy Man.
The Galaxy Man stage is one of the easier stages, so it's a good place to start.
Begin by running to the right.
Some green UFOs will fly around, avoid or destroy them with one shot from your Mega Blaster. Then climb up two ladders found here.
Continue to the right. You will find some Mets.
Once you are close enough they will lift their hardhats and attack with a triple shot. Kill them quickly before they lower their hardhat again. If you are quick you can kill them before they get their attack off.
Carefully jump down to the second Met. When you jump, hold to directional pad to the right to keep from falling in the spikes, otherwise it's instant death. Don't stand too close to the edge or the Met may knock you into the spike pit.
Continue to the right. Be prepared for more UFOs.
Climb the ladder.
Jump to the middle platform, right above the spikes. Careful not to fall in the spikes.
Jump over the spike pit, using the ladder as a grab point if necessary.
Defeat the Met under the ladder and climb up.
Jump over to the floating block.
Jump from the floating block to the ladder and climb up.
There are two floating teleportation devices in this room. Jump into the one that you can reach.
You will notice that when you enter the first teleportation device, you will bounce up out of the second one.
Enter the second teleportation device and you will bounce out of the first one. Hold the directional-pad to the left and push up to climb the ladder.
You will find a grasping robot here. If it grabs you, it'll force you rightward for a while and eventually will let go. This won't hurt you here, but up ahead these robots can force you into spikes.
Climb the ladder and jump over to the large health bubble if you need it.
Head to the right and jump down over the spike pit.
If you keep running to the right, you will come across more of the grasping robots. Some of them will take you right into a spike pit, so we need to avoid them.
Walk slowly to avoid them. They will fall in front of you and harmlessly fall off the screen. Then continue on to the right, but be careful because there are a few of them.
Once you make it past all the pits, climb down the ladder. You can drop too (the last grasping robot will force you to), but make sure you hold the d-pad left to avoid a spike pit below.
Drop down the ladder and climb up the other ladder that leads to a Met to destroy.
Drop down here. You can grab the large weapon energy bubble in the right indent if you need it. Hold the d-pad right as you fall to avoid another spike pit.
More UFOs will fly at you. Don't stand too close to the spikes are they may knock you in. Destroy the UFOs, then climb the ladders and head right.
You will come to more floating teleportation devices. There are six of them, three pairs. Each one will only take you to it's pair and vice-versa.
Bounce in and out of the teleportation devices until you find one that comes out over to the right. When you bounce out of this one you'll have to carefully steer left of it and then make a hard right to land on the ground safely. If you fall in the pit it's instant death. Continue right.
Here there are three circular robots blocking your path.
Shoot the robots. They will split into four smaller robots. Do your best not to get hit and destroy or avoid all of them while climbing upward.
Once the robots are defeated, climb up the ladder at the top.
Two more robots, just like the green, circular ones you fought on the last screen.
Destroy the closer of the robots and then jump over to the center platform. If there are any robot fragments left they could knock you into a hole.
Open up your inventory and choose your Rush Coil.
Press your attack button to drop your Rush Coil in front of you. Jump on his back and he will give you a high bounce upward. You want to hold the d-pad to the right as you bounce upward so you can reach the ledge with the extra life.
Carefully jump back down to the center platform.
Switch back to your Mega Buster weapon.
Destroy or avoid the second circular robot and climb the ladder upward.
There are two circular robots and two red shield robots as well. The shield robots are fairly fast and go back and forth along the platform.
Shoot the shield robots in the back to defeat them.
Climb up the ladder and head right.
You will come across another grasping robot. On the bottom level it isn't dangerous. Keep heading right.
Destroy the Met and jump to the platform where it was sitting.
Jump over the spikes and head left.
Move slow when you get closer to the ladder to avoid the grasping robot or he will drag you into the spikes to your right.
Climb the ladder and head right, destroying the Met.
Climb up the ladder.
There are two screws in the bottom corner of the room you can collect. The screws are used at the game's shop. You can use them to buy extra lives, energy tanks, etc. Also avoid the UFOs.
Climb up the ladder to continue.
Destroy or avoid the UFOs found here. There is a weapon energy bubble, but approach slowly if you grab it, there is a grasping robot ready to drop down on you. If you do grab the weapon energy, first select the weapon you want to charge from the weapon menu (the only one we've used so far should be the Rush Coil), otherwise it won't charge anything.
Jump up the platforms and head left at the top if you want a health bubble.
Approach slowly to the health bubble to avoid the grasping robot.
Continue rightward. There are more UFOs to destroy or avoid.
Jump in the teleportation device.
When you bounce back out of the first teleportation device, you can fall past it to the right and then sharply press to the left to land on the platform and grab the large screw. Jump back into the teleportation device after you collect it.
Continue bounce in and out of teleportation devices, moving rightward. Don't let the flying UFOs knock you into a pit.
Jump up to the ledge on your right. Continue right. This is a door to the first boss battle.
The empty halls before the boss battle give you a chance to change weapons and such. They also act as a continue point, should you die (unless you run out of lives completely.) Walk through the door on your right to enter the boss' room.
Galaxy Man, your first boss battle.
Galaxy Man will fly in the air a lot and drop his Black Hole Bomb. The bomb will slowly fall toward you.
Do the best you can to run away from the Black Hole Bomb.
Galaxy Man will appear right under the Black Hole Bomb for a short bit. Avoid touching him to prevent damage.
When you get used to the timing, you can turn around and get a few shots off before Galaxy Man disappears again. Then the cycle will start over.
Every once and a while, Galaxy Man will come to the ground, allowing you to pelt him. Sometimes he will fly at you afterward. You can jump over him to avoid getting hit and then shoot him some more.
Keep using those tactics until you defeat Galaxy Man.
Now that you've defeated Galaxy Man, you will get his weapon.
Save your game if you desire, then choose state select to continue the game.