Just tried the GBA version of Iridion II.
There are 3 difficulties: Starter Pilot, Advanced Pilot, and Ace Pilot.
3 modes: Story Mode, Arcade Mode, and Challenge Mode.
And 3 options: Gallery, Jukebox, and Credits.
I picked Advanced Pilot and Story Mode. Iridion II told me this story in a Star Wars intro scroll.
>More than a hundred years have passed since Earth has been attacked by the vicious IRIDION forces.
>The legend tells a single brave SHN Fighter Pilot found his way to destroy the evil IRIDION mainframe.
>After this glorious victory all remaining enemy ships disappeared from known space.
>So humans began to colonize the Planet Systems of the IRIDION home galaxy.
>Peace and freedom came back to mankind. The IRIDION menace was history.
>... until now.
Then a commander told me this story.
>Here's the situation. The evil Iridion forces have regrouped after their defeat on Iridion Prime a hundred years ago. They have come to reclaim their planets. We can't allow this to happen. We need someone to defeat them once and for all. I was told you were the best. Complete the Virtual Reality Training program to prove that you know how to handle your SHN fighter. Once familiar with the controls of your ship, head to the ALPHA Galaxy.
The tutorial explains the mechanics: your space craft is capable of autofiring by holding down A. If you double tap and then hold A you can release a powerful beam. To upgrade your weapon system you need to collect power-ups. Power-ups are carried by special enemies. Those enemies must be destroyed before they'll drop power-ups. After collecting power-ups press B to upgrade your current weapon. After you upgraded a weapon your spacecraft will be extended by two satellites. The satellites can be moved up and down when releasing A. By holding A the satellites' position is fixed. Press Select to lock the satellites to their current position. Press Select again to unlock them. After collecting a power-up and before pressing B you also have the choice to change to a different weapon. Press R/L to select your desired weapon. Each weapon can be upgraded three times. You can change to already upgraded weapons at any time by pressing R/L. Whenever you start in a level you are equipped with one smartbomb. Smartbombs are also occasionally floating around and waiting to be collected. To release the smartbomb press R and L simultaneously.
In the ALPHA Galaxy I chose and completed Azuki Canyon in 4:16 with 11370 points before bonuses, like a life bonus of 4500 and a smartbomb bonus of 1000. My rank sucked (rank C), as I spammed bullets, which ranks punish with an Accuracy bonus.
Iridion II's a fun shmup I'll probably finish.