All Clear! Trophy
Cleared Arcade mode with ending A.
There are two ways to unlock that one.
To reach ending A the normal way, there are a few requirements you have to fulfill. Remember the Emergency Call? You have to complete all 4 of them in one playthrough to advance to stage 14.
1. Emergency Call, stage 3 (Canyon Grandeur): As described in "Emergency Call", you'll have to destroy the Prototype.
2. Emergency Call, stage 6 (Golden Valley), only accessible if you've killed the Prototype: This time, you will have to destroy a stealth bomber. Stealth Bombers can not be locked on to to hit them with missiles, so you'll have to destroy him using your gun. Use Climax Mode to make it easier to aim at him while dodging cliffs and enemy attacks. As long as you keep up with him, you get the chance to destroy him during the beginning of stage 7 if you can't destroy it during stage 6.
To make things easier for yourself, keep choosing the right path from now on.
3. Emergency Call, stage 8 (Forgotten Glory): This time, your task is to destroy 10 Helicopters that are marked with the same "Target" sign as the Prototype. As long as you use to slow down and destroy the helicopters with your missiles, you'll be fine. There are more than 10 Target Helicopters, so if you miss one you can still accomplish the task.
4. Emergency Call, stage 13 (Nuclear Arsenal): This one may be a bit tricky, but if you hold down and press the climax button shortly before you enter the first tunnel you'll be able to lock on to the target, a nuke carrying jet. Fire as many missiles as possible as you have to destroy it before you enter the second tunnel. Once you enter the second tunnel you won't see the target again. But as long as you use the above described method, you should get it.
Once you're in stage 14 you'll have to shoot down rockets with the gun as your missiles do not work. Shoot them and you'll progress to stage 15, where you will have 30 seconds to destroy another rocket. If you can make it, you'll see the A ending and the trophy will unlock.
The second way is to force the entry into stage 14 using the EX-Options again. To unlock the Ex-Option that forces stage 14 you'll have to complete 20 Emergency Calls first, though. They're accumulative so you can do them on multiple playthroughs. Once you reach Stage 14 in Arcade mode with the EX-Option on, it's the same as if you've reached it the normal way, shoot the rockets, see the A ending and the trophy will unlock.