You will unlock this achievement when you finish all 13 missions on the Formidable Difficulty as it says. This achievement is also stackable.
So with that being said unless you really like this game and want to play it a few extra times I do not recommend playing the game on the Normal Difficulty setting. Instead play on Easy (to get used to the game, do all the hero objectives, get the other ash and trash achievements, and to unlock all the armor types) and then play it on the Formidable Difficulty (hardest) to get this achievement and the "Hero" Achievement. The main reason why I recommend playing Easy mode first is because you will get all the armor types for the Formidable Difficulty and you will have a better understanding of the game.
So just to be clear, before you start this achievement and switch to this difficulty you should have EVERY achievement but the "Hero" achievement and this one (Super Hero).
The mission guide below was written by me and explains how you beat a mission on the Formidable Difficulty. This is a LONG guide (sorry about that but it might help someone out that is stuck).
WARNING: The guide is written as if you already played the game in easy and unlocked all the armor types.Remember you get four reboots per mission.
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Mission 1: Escape
============================This is your first mission. This mission is pretty straight forward and does not allow you to pick any suit types (your forced to wear the clunky iron suit with no real abilities).
The most thing you will be concerned about is your low amount of health. Try to move quickly to your foes and defeat them with your flame thrower or melee attacks. Take cover to heal behind buildings to heal. Ideally you want to try not to lose any reboots until you reach the boss but if you lose 1 or 2 you will still be okay.
The boss fight is not too hard as long as you have at least 1 or 2 reboots left. Try not to shoot the fuel tanks unless Raza is next to one. The largest issue you will face is the helicopter that re-spawns, when you see the helicopter take it out with a missile ASAP, it can kill you fairly quickly.
Use your missiles as soon as they are available on the tank and also watch out for the opportunity to shoot a fuel tanks when Raza is next to them. The tanks cause major damage to the tank boss.
This mission is not too hard. I finished it my first time.
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Mission 2: First Flight
============================Leave your Power Distribution set to Life Support (up on the d-pad) the whole level (except when they ask you to for the tutorial).
The first part of this mission is of no concern since it is just a tutorial on how to fly.
After you finish the flight tutorial you will be prompted by Pepper and you must protect Stark Industries from being attacked. Mostly these are of no concern you will defeat several groups of ground troops, then destroy six or seven transport vehicles, and then you will have to take out several transport airships while fighting off helicopters. The helicopters are your main concern since they can tear your armor up pretty good. Ideally you want to not lose a reboot up until the boss fight however losing 1 or 2 is just fine. After you defeat the transport airships (or they leave) the boss fight will start.
You will have to take out the Gunship (the boss). This poses no issues as long as you at least have 1 or 2 reboots left. Easiest way to take him out is by the air, the gunship cannot be grappled. Keep your distance and constantly fire your repulors (hold RT) and use missiles (press Y) when available. IGNORE the drones.
Overall this mission is easy. I finished it my first time.
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Mission 3: Stark Weapons
============================This is the first mission that you can select which suit type you want to equip.
Recommend Suit: Silver Centurion Suit.
Recommended Power Distribution: Life Support (up on the d-pad) the whole level.
This level starts out with the objective to take out 7 warehouses filled with weapons (each warehouse is marked as a orange dot on your radar). Approach these warehouses with caution since you can die pretty quickly if you rush in. Best way to take out all the enemies is to hover, take your time, keep your distance, and take cover (land behind something) to heal when needed. I recommend taking out most, if not all, enemies in each area.
The next objective is to take out several conveys, just fly to their location and shoot them with missiles. This is super easy if you took out most of the warehouse enemies early on. At this point you should have lost none or just one of your reboots.
The boss fight is with this super tank (I don't know what else to call it!). It has more weapons then space (I think they built a bigger tank just to house more weapons!). If you have 3 or 4 reboots you will have no problems. There is two ways to fight this massive super tank...
1. If your like me and have all four of your reboots, trail behind it and blast the heck out of it (hold RT and press Y every time your missiles are ready). You will die a few times but you will have enough reboots to waste him.
2. If you don't have all your reboots or you want to make sure you win. Trail behind the super tank and take a few shots, hide and recover your health... repeat. At one point the tank will stop moving, move to the top of the valley and shoot him from the top of the valley, land on the ground (on the top of the valley) to heal when needed.
Not too hard of a mission if you take your time and be smart. I finished it my first time.
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Mission 4: Maggia Factories
============================Recommend Suit: Silver Centurion Suit.
Recommended Power Distribution: Life Support (up on the d-pad) the whole level.
This one is fun! First you must take out 4 control centers. You just need to take them out and you don't have to kill the forces. Just fly as fast as you can to the Orange dots, land as fast as you can next to the building and melee it 3 or 4 times to destroy it then fly out as fast as you can, hide and heal. If done correctly you will lost no reboots but it's okay if you lose one during this part.
Next you will have to destroy several helicopters and tanks near the main site. This time you will want to take your time and heal when needed. I attacked from the south end and healed in the valley when needed.
Next you will have to take out four factories. There will be a fuel tank next to each factory. Use fly as fast as you can, hit the tank, and then jet out of there. You should not lose a reboot if done correctly but losing one here is okay.
The boss fight is not hard at all as long as you have 2 or more reboots left. If you have all four or three reboots left just hover above this tank and hold RT and use missiles when available. Ignore the choppers. If your low on reboots, land on the ground, shoot the boss when you can, take out any choppers that are hitting you, and heal behind the buildings.
This mission is hard to get used too, I had to play it three times to get past it.
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Mission 5: Maggia Compound
============================Recommend Suit: Silver Centurion Suit.
Recommended Power Distribution: Life Support (up on the d-pad) the whole level.
This level sucks. Don't worry about taking out random enemies too much. You will have to destroy 10 defenses to move on. Just fly in as fast as possible, take them out, and fly to the next one (try to find a valley or rock to hide behind to heal). Ignore the missiles they are well guarded and optional. You will have to use at least 2 reboots, if not your doing well!
With your remaining 2 (or 1 reboot) your going to have to destroy the core. Doing so is easy. Just fly into the valley from the south or southwest side. Take out the enemies quickly on that side (don't worry about the other side). If your on the correct side you will see the core on the left side and a little fenced in area to the right. Fly over there and land inside the fenced area. If your in the right spot no one can hit you. Just hover up, shoot the core, land when health is low to heal up. Repeat until mission is over.
Hard but with the help of the hiding spot it is much easier.
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Mission 6: Flying Fortress
============================Recommend Suit: Hulkbuster Suit.
I love timed missions (not!).
Once you start press LEFT on your d-pad to power your thruster and fly like a madman to this large Flying Fortress (these guys have too much money!). Once you start to get close to it, you are going to have to switch to life support (press UP on the d-pad) and start going doing flight maneuvers (go left, right, up, and down) to avoid the blasts. Head to the left of the plane and land as soon as you can. Take out any turrets or choppers in your way, take cover and heal. Take out the remaining anti-air turrets (there are 10 in total). Work your way from the top left to the top right of the ship, make SURE you destroy the pad the choppers are coming out of (there is two of them on the top middle) or you will not last long. Once you destroyed all the AA turrets on the top move to the bottom and take out the AA turrets from right to left. Try to avoid hovering for long times, the ship is moving. If you lose one or two reboots that is okay but is possible to do without losing any reboots since the Hulkbuster is so good with armor.
Next you will have to destroy four hangers. This is super easy. Fly to the top front of this flying hunk of metal. If the hangers are open, great! Shoot the fuel tank inside and BOOM no more hanger. If the hanger are closed don't worry. Just stand 10-15 feet away from the hanger, look at the ground near the hanger and press Y to launch a missile. If done correctly you will destroy it. It might take some practice but it works well after you know how to do it. You should lose no reboots during this part.
Next take out the cooling units. There are four of them. Fly to their location, I recommend flying above the ship and not below it. They are located in the middle part of the ship. Destroy them as soon as possible, when traveling to the next one remember to fly above the ship. You can lose one reboot but I recommend not losing any (it can be done pretty easy).
Next are the four tanks. Fly above the ship to the back and lo and behold an open door! You can either hover above the opening, drop down shoot some stuff and fly back up to heal OR you can land on the very back of the ship and hover up and shoot some stuff, land to heal. I found landing is better. Remember the ship is moving, try to keep up.
Lastly, and the most easiest, is the reactor. Fly to the top end of the ship in the middle. Land inside the opening next to the reactor and blast it. I had two reboots left but did not need any.
This is the third to hardest mission in my opinion.
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Mission 7: Arctic Battle
============================Recommend Suit: Silver Centurion Suit.
Recommended Power Distribution: Life Support (up on the d-pad) the whole level.
Okay here we go. An option is to use the Hulkbuster suit however I found him too slow and it was MUCH harder to hit the end boss with him.
NOTE: There is PLENTY of cover for you in this mission. If you fly on the boarders of the map you are protected from enemies, huge lasers, Titanium Man, etc. Stay behind THEM ALWAYS when traveling from one location to another.
This level sucked for me so I hope I can help anyone out that needs the help. The mission starts off with the objective to destroy the anti-air turrets. There is at least 9 of these. Take your time, keep your distance, and take cover to heal when needed. You can, if your careful, complete this part and not lose one reboot however if you do it's no big deal.
Next it's laser dodging time... If you are wearing the Silver Centurion Suit and get hit by this laser you die (in formidable difficulty). Period. The laser cannon has a stellar aim and never misses (unless your hiding behind something). You now must dodge the laser and take out it's power stations to disable the shield around the laser. Use the valleys and mountains as cover and when you get to one of the power stations land NEXT to the power station so that the building itself is in-between you and the laser. Take out any enemies that can see you (don't worry about taking them all out) and when you hear the laser charge do a quick hover shoot the now open power station with a few repulors and one missile and then land real quick to dodge the laser blast. Repeat for the rest of the power stations. Remember to fly along the mountains and valleys when traveling between power stations. You can make it without using a reboot but it's okay if you lose one here.
After that it's time to take out the laser. If time runs out, that is okay, it's an optional objective. The best position is to sneak up behind it on the mountain side and attack it, hide behind the mountains to heal when needed. Again, if you lose a reboot here it's okay but if your low on reboots try to stay hidden pretty well. If you take your time you don't have to lose a reboot.
Lastly you need to destroy Titanium Man. Use the same trick on him as the laser. Use the mountains as cover. He does heal so your going to want to be semi-aggressive. If you have all or most of your reboots you can just blast him away but if your low on reboots (like I was) you can just take your time. If your using the Silver Centurion Suit even if he heals you still will beat him as he will lose life slowly and eventually will be defeated.
This level was one of the hardest one's for me. Good luck and take your time!
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Mission 8: Lost Destroyer
============================Recommend Suit: Silver Centurion Suit.
Recommended Power Distribution: Life Support (up on the d-pad) the whole level.
TAKE YOUR TIME ON THIS MISSION. Use the mountains as cover, use rocks, buildings, and anything else you can see. I won this level the first time by just being SLOW. The enemies are strong and come in forces. Their weapon reach is long and are accurate. Watch out for the mortars while your healing behind something.
You will have to take out four bases. You will need to take out everything that is orange to defeat a base and what it seemed like to me, reinforcements come often so you have to work quickly. Watch out for the subs and the big ship (the smaller one inside the base is not an issue) while doing this, they fire about 10 billion missiles at you at once if they see you. If you take your time you can get away with very little reboot loses. I am going to say if you lose 2 reboots during the course of taking out these four bases you will be fine. If you lose 3 your still okay but you just have to be careful on the final boss.
The final boss is a sub that seems to have a semi-auto missile firing gun with lasers. You can't take this thing head on so fly to the top of the valley and land on the ground. Your going to hover up shoot a few repulors and then shoot your missile (y button) and then land. Once your missile is read to use repeat the process. If you need to heal just land do so. The sub will go under and go to another location (there are only two locations so once you learn them you can fly over and beat him to it) so follow him and do the same thing (fire, cover, heal, repeat).
This mission was not too bad because I beat it the first time because I was slow and careful.
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Mission 9: On Defense
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Recommend Suit: Silver Centurion Suit.
Recommended Power Distribution: Life Support (up on the d-pad) the whole level.
Simple mission. Kill Titanium Man. You don't have to worry about cover in this mission. Just blast him (hold RT down and press Y while missiles are refreshed) to death. Follow him like a hawk and focus all your attacks on him. He should die (if you hit Y every time) before he starts to fly off to the second power grid.
Easy as pie... just does not taste as good.
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Mission 10: Save Pepper
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Recommend Suit: Silver Centurion Suit.
Recommended Power Distribution: Life Support (up on the d-pad) the whole level.
NOTE: If I use the terms right, left, front or back I am referring to the large Research Facility you must protect. Image yourself on top of it, the front would the the part facing the land and the part facing the water is the back. The right would be the part to your right when facing your facing the front and left is the same idea.
This level is very hard. It took me two times (almost a third or more but I got lucky). Here is what I have to offer...
At all costs, you must protect the research facility. Most of the enemies will attack this building and if they blow it up Pepper gets blown up too... and from the name of the mission that is a bad thing. You don't have to worry about reboots because most of the enemy fire is at the building. If you fly through the green hoops (sorry I forgot their names) you will kill most of the missiles and enemies attacking the building if they are within range. So when you hear "Overloaded" they are active and doing their job, when you hear "Stabilized" you can fly through another green hoop and reactive the power surge.
Once you start the mission, fly straight ahead and you will see a green ring looking thing, fly through it on your way up to the research fac. Your main goal is to save that building. Be aware of the hovering enemies that attack it. Most of them will attack from the left and front sides but be careful and watch your radar! Several will sneak up and attack from the back and if you don't pay attention you will regret it later. Once you get that first part done here comes the missiles. Use your repulors and missiles (Y when ready) to take them out. Aim your best. Remember you still have to take out the hovering crafts too but focus on the missiles. Ignore the secondary missions.
The last part is pretty easy if you make it that far. You will hear something about "multiple warheads" This is you hint to GET on top of the research fac and get ready for some missile killing. they will come from the front right and front left. Use your RT and Y all the time. After the missiles stop your done! RELAX!
Very hard mission. One of the hardest.
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Mission 11: Island Meltdown
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Recommend Suit: Silver Centurion Suit.
Recommended Power Distribution: Life Support (up on the d-pad) the whole level.
NOTE: In this level there are jets that bomb you in this level (like some of the other levels) but this time they can almost kill you if not kill you in one pass-by. So I HIGHLY suggest killing them and no, they do not respawn.
NOTE 2: If you go under water, missiles stop pursuing you. Helpful when travelling between couplings (Thanks goes to Capn Doug x360a for that!).
Act quick in this level. You first must destroy the power couplers however if left alone too long they will regain power again. So this is what you have to do. The first area you see (straight ahead) is the base on the east. Fly over there and take it out, don't worry about the enemies too much, just take out the coupler, hide and heal when needed. After that fly away from all enemy contacts and wait for the jet to do a fly by, take them out with repulors and missiles (you will have to hover to reach them, if you die just restart if you want since your so close to the beginning). Once they are taken care of attack the south, west, and north power couplers (in that order). When going for the west and north couplers go by the water, also if you attack the couplers from underneath you will usually find a spot where you can attack the couplings without having to worry about any defenses (thanks goes to Capn Doug x360a for that!). Again don't worry about the enemies just focus on the couplers and move QUICKLY. I found it best to be semi-aggressive and fly down by the water and not up by the land (less turrets, except on the north base). You can lost at least 2 reboots before starting to worry.
There are two methods to this last part:
METHOD ONE (the one I used because I did not know any beter): After they are taken care of time to take out Horgan and that large laser of his. Best thing to do is fly to the middle base's southwest side. Hover in that corner near the edge of the base (so when you need to heal, just drop down/land). Take out Horgan first with RT and Y (you may want to take out that one turret on the structure first) and watch out for jet-pack men with rockets. After that take out the laser. Easy if you watch your health and heal when needed.
METHOD TWO (thanks goes to Capn Doug x360a for this): You almost don't need to bother attacking Horgan, since if you take down the laser, the mission ends.
Not too hard, took me a few times but after I learned to kill the jets first it was much easier.
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Mission 12: Space Tether
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Recommend Suit: Hulkbuster Suit (NOTE: I have been told the Silver Centurion Suit is best for this level but it did not work out too great for me, please take this into consideration when selecting a suit for this level).
Recommended Power Distribution: Life Support (up on the d-pad) the whole level.
Okay here we go... Hulkbuster all the way. There is way too much firepower for the Silver suit especially at the end when the never ending spawning rocket men are coming. When you have the Hulkbuster Suit on it makes it nearly impossible to hit the jet-pack rocket men so just ignore them, they don't do much damage to you anyway.
There are four defenses you need to take out. Each one is heavily guarded and they can do some real quick damage even to the Hulkbuster. So take your time and use cover ALLOT. Take out all the enemy forces and then take out the defense objective. Once you start the mission go straight to work on your first base, use the mountains and structures there for cover. Once you finish with that, work your way to the right, stay in the valley for cover. If needed fly out of the valley and go the the mountains on your right. Take out all four this way (use valley first and then use the mountains on the right for a different vantage point if needed). You can lose one or two reboots but should not have too.
Next your going to have to take out the control boxes. There is four of them. Ignore all enemies (because they respawn anyway) and take them out, don't worry about cover either since you have good armor. Just focus your full attacks (hold RT and use Y when missiles are ready) then move to the next one as soon as possible. Once all four are done you can move to the very center of this structure. You can lose one reboot on this one with no concern.
Now you have to destroy the inner guts of the defenses. Just hover around and focus all your attacking power on these defenses. If you get low on health you can land on the ground and you will see a little entrance looking holes at the base of the structure (there are four of them). You will be completely safe inside there. Once your done with the center defenses fly to the very top of the structure and take out the tether. This is very easy and you should lose no reboots.
First time after I used the correct armor!
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Mission 13: Showdown
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Recommend Suit: Silver Centurion Suit.
Recommended Power Distribution: Life Support (up on the d-pad) the whole level.
I tried this mission with both the Silver Centurion Suit and the Hulkbuster Suit and I recommend the Silver Centurion Suit.
This mission is pretty much straight forward. Keep your distance by hovering away (I fly for the whole level except where you have to land to melee him). Right at the start of the level your going to want to focus everything you got on him (hold RT and Y when missiles are ready), hover away from him and towards some building for cover. Keep your distance and when your low of health hover behind a building for cover. I recommend when he is charging hide and when he is firing missiles go ahead and take the hits (with full health) to get a few shots in. After you take him out 5 times he will be on the ground helpless. At this point if you only lost 2 or 3 reboots your doing good as long as you have at least one reboot for this next part. Fly down behind a building, heal and get ready for a rush attack. When you think its a good time rush out (use A button for a thruster dash) and when you get close HOLD the B button to grapple him, you might need a reboot based on how far away he landed from the building. Once he is grappled and you mashed the B button your pretty much home clear.
Lastly you will need to destroy four power regulators on top of a building, they are easy to take out. Just get there as soon as possible and focus your attacks on them.
Once you finish those.... GAME OVER!
WTG ACHIEVEMENT UNLOCKED!
If you have not already, you will unlock these three achievements as well:
The Hero achievement in Iron Man worth 220 pointsComplete all missions on Normal difficulty (or harder)
The Sidekick achievement in Iron Man worth 141 pointsComplete all missions on Easy difficulty (or harder)
The You're Fired! achievement in Iron Man worth 47 pointsDestroy power regulators in the Iron Monger mission