Air Date: December 11, 2019
For a detailed strategy check out my guide on gamefaqs( https://gamefaqs.gamespot.com/ps2/918889-fullmetal-alchemist-and-the-broken-angel/faqs/77594) ).
After your fight with Camilla and the ultimate chimera, there is an optional boss fight with Roy Mustang and Major Armstrong in front of the alchemy works. While you can throw the fight and get the same ending, they do have some unique items up for grabs if you can defeat them. You will get a Sun Medal accessory for winning the fight but you can only walk away with the accessory drop from the enemy that you defeating first in the battle because the fight ends immediately after you land the finishing blow on the second fighter. This means you will have to engage this duo twice in order to pilfer all the available items. In the video, I show you the method I go about the Demon Fist accessory from Armstrong, which is the easier of the two items to obtain in my opinion. Armstrong, as opposed to Mustang, likes to stand there and soak up damage from consecutive hits. In order to capitalize on this we will be using the two transmutable tanks but will also have a boomerang handy for ranged combat if the tanks fail.
We will need to do a little prior homework in order to have a boomerang available during this fight. In the first fight in the castle keep against the three chimeras, you will need to transmute a boomerang from the spear object in the arena and grab ahold of that before you finish off the last of the three chimeras. This will allow you to carry the weapon to the next fight with Camilla and the ultimate chimera. Feel free to drop the boomerang in this battle in order to fight the pair of bosses. Just remember to pick the boomerang back up before you gather all of the feathers following the fight in order to carry it into the Mustang and Armstrong fight. Refrain from transmuting the boomerang into the chakram because they hit for less or apply any elemental attributes to it. In addition to the fallback boomerang, we will want to make sure that we have plenty of reloaders for the two cannons. Provided you horded most of these during the game you should find yourself with a decent amount to last the fight. If you wanted more you could always farm the bug enemies during the water chimera fight or collect random drops from enemies in the dining room and hallway areas near the beginning of the castle.
Some other preparations include having at least one Alchemy capsule, one defense capsule, the double-edged armor, the double-edged earrings, and as many restorative items as possible. Having a high-level character will also help along with any of the tall boots, moon medal, or sun medal accessories (if doing this battle for a second time). If your alchemy stat is high enough, you might be able to get by without the boost from the double-edged earrings.
Dodge to the right immediately to avoid the opening attacks from the duo at the start of the battle. At this point, you will want to maximize Edward’s alchemy power by using an alchemy capsule and equipping the double-edge earrings if needed. Alphonse will serve as another target during the fight so he gets the defense capsule and the double-edged armor. You will note that we are not using the magic capsules for this fight. Magic capsules increase everything by 10% and the more specific capsules will increase the targeted statistic by 20%.
During the fight, you will want to keep both party members alive and immediately resurrect Alphonse if he falls. You might have to lure the bosses away from him to do so. Try to keep your distance by alternating between both sides of the battle area and use the L2 button to toggle your map to the close up version. This way you can see where your two attackers are by the white radar dots.
First, transmute both tanks on the opposing sides of the battle area. The idea will be to hop into a tank when your foes are a good distance away and fire away at Armstrong and then retreat to the opposite side to repeat the process, reloading the tanks as needed. By continuously alternating sides, you keep the enemies at a distance and gain additional time for attacking or reloading.
Mustang tends to tail you closely so feel free to hit him with a tank shot before laying into Armstrong. Normally they will be close together so a single blast will hit both, launching Mustang into the air and allowing you to sink more hits on Armstrong. As you continue the strategy, keep the tanks from absorbing too many hits. Safely get in a couple shots and then get out of the tank before they attack while you are inside it. Avoid a tank if they are too close to you. With a high alchemy statistic, a tank hit on Armstrong will do around 150 damage with a maximum of ten hits before reloading. Once Armstrong falls make sure you grab the dropped demon fist accessory and then attack Mustang with the tanks.