Well, since no guide exists on the subject, I’ve decided to make one. All missions were completed on Medium. Suggestions, comments, and questions are welcome.
Note that this is a Battle Tactics mission guide only. It’s not for OTA or multiplayer. My Core Contingency guide is here.
Read the briefings, by the way. They usually contain good info and strategies. Just ignore any survival times, as they’re always wrong. Destroying enemy units wins the battle, not waiting out a timer. CORRECTION: If a survival timer exists, it must be waited out, even if no enemy units are on the map. If any enemies exist after, they have to be destroyed to end the mission.
ARM Very Short: 14/14
*Charging the Line: Start moving south immediately. Destroy any units that are directly in your path. When you reach the southern corner, build a rader, Kbot Lab, and solars. Hold this position until you’ve destroyed three Goliaths and then head to the base.
*Dawn Directive: The Aircraft Plant in question is southwest of your current position.
*Waiting: There’s a metal patch due north of your position. Just be quick about D-gunning the Gaat Guns.
*Vulcan’s Forge Hotspot: Flashes, Flashes, and more Flashes. Just keep harassing the enemy until there are no more. Keep moving and your life will be much easier.
*Crawling Destruction: There’s a lot of Roaches here. Unfortunately, we don’t have a shoe large enough to squish them all. Fast units are key here. Keep just in range, and your units will take minimal to no damage.
*Battle of Ansap Sea: Just send your navy south. It’s powerful enough to destroy anything fool enough to come close to you.
*Between Two Lakes: There’s a few enemy units to the east, so deal with those before heading north. Focus your fire on one target at a time. Try to keep the most heavily damaged units in the back.
*Hunting Nhanons: Take all of your units and head north. The Advanced Aircraft Plant is in the northeast corner.
*Sub Hunting: The enemy subs come from the north and south. Just one comes at a time. Fire your torpedoes and immediately move your subs to avoid the incoming torpedo.
*Ambush on Novespin IV: Ignore the briefing. Take all of your units and sweep the map. The objective is the Construction Vehicles, so prioritize them.
*Force the Strait: Basically, Ctrl-A and order them to destroy anything that shoots back. Prioritize AA weaponry to help your Brawlers survive.
*Destroy the FMD: The FMD is in the very back of the enemy base, at the center of the western edge. Hotkey your attack force, scout the FMD, and then send them all in.
*Kaki Island Assault: Load your commander into the Hulk and send all your Tritons south. Destroy anything foolish enough to get in your path. The Geothermal is at the southern tip of the island guarded by a few Gaat Guns and Pulverisers.
*Fighting Under Fire: Build a few more Mohos to support production. Get to the western ridge and build Fortification Walls, Advanced Radar, and Big Berthas. There were two operational cannons along an inner ridge across the gap. A third was under construction further in. Peepers will help you find them and the Advanced Construction Kbot building the third.
ARM Short: 17/17
*Zipper Attack: Get moving right away and stand still as little as possible. +shootall is useful. I moved counterclockwise through the base and managed to hit all the targets. Just keep searching. If it helps, make yourself a map of all known target locations. You may have to repeat this mission a few times to get it right.
*Can Rush: There must have been at least twenty Cans incoming. Not good. Move fast. You don’t have much time before they crash into your line. You have three Construction Kbots. Going counterclockwise from the northeast corner, have the first work on some Sentinels. Move the nearby Hammers up to guard it. The second should seal the passage next to it with Dragon’s Teeth and then assist the third. More Sentinels from the third, but queue them in a line going from the Dragon’s Teeth towards the Fusion. Once the orders are given, just move your forces to intercept as well as you can. The attack mostly goes counterclockwise around the base, but a sneak attack comes from the northeast with a Deleter in tow at the end. Keep your units as far from the Cans as possible while still hitting them and you should be fine. Remember that losses are acceptable. I lost much of my mobile force and still won. Also, make sure you get the Deleter. The mission doesn’t end until it’s also gone.
*Attack on Barrack: Take your forces west, but approach by a northerly route. If you come through the south, you’ll take severe losses. When you reach the Dominator horde, pass right through and hit the Advanced Kbot Lab producing them. Knock out the laser tower defending it, but ignore the mobile units. When the Lab is gone, clear out the Dominators, remembering to keep moving.
*Cutoff in Sector 6598: Build some solars and metal extractors, and clear out the enemy outpost to the north of your position. Then build a Radar Tower and clear out the enemy to the west, one target at a time. Use the Penetrator. Keep some units at the southern end of your base to guard it. When the western units are gone (except for the ones in the corner, they can’t be reached, but can be ignored) deal with the units in the south. The main thing is to remember to keep that D-gun powered.
*Encounter on the Coral Sea: Radar targeting is critical here. There is a significant Core navy, but it can be destroyed with minimal casualties if you focus fire. Keep the Skeeters alive, as torpedo bombers are a pain. The base is in the southwestern corner. Again, radar target, especially dots that are on their own. There seems to be only one shipyard.
*The Wayneston Ford Engagement: Set your units to return fire. Destroy anything that can attack you that’s on the west side of the river, but capture the Core Construction Kbot running around. Capture the solar and Metal Extractor and set the Kbot to build solars. Then head to the northern edge of the map, head over to the east bank, and head south. Stay close to the eastern edge as you head south. Capture or destroy the solars and Energy Storage that you encounter. Don’t tangle with the defenders and you’ll be fine.
*Ice Base Baryn: Take your some of your southern units and clear out the enemy units to the south, which includes a Silencer! Don’t worry, it won’t fire. It doesn’t get a chance. 
Keep them to the west to guard your Construction Kbots while they cap the deposits. Build two more Construction Kbots and queue lots of Peewees. Have some Construction Kbots reclaim while one builds the Advanced Kbot Lab. Build it near the Kbot Lab for maximum protection. Your forces can deal with what enemies attack with a minimum of micro.
*Forest Base 129: There are factories in the northeast corner, the western island, and the center of the southern edge. Focus fire on Gaat Guns and factories. Ignore anything else that gets in your way.
*Rock Candy Mountains: The first Radar Tower is north of the northwestern position. The second is east of the southern position. The third is in the center of the map. The exact locations are hard to describe, so search for them. Keep units near your Radar Towers to ward off any attackers that come too close.
*Kudzu Base: Build two solars and a radar tower. +shootall is useful in this mission. Use the radar to find targets. Build more when you need them. The only danger to you is the Sentinels, but they’re easily destroyed. All of the Metal Extractors are on the land, which is the eastern 2/3s of the map, so don’t look past that.
*Yerrot Foothills: Build two solars and take your forces east along the southern edge. Stun anything that gets in your way and move on. D-gun if your commander is close enough to do so without destroying your own units. The Advanced Aircraft Plant is on a mesa with some LLTs, Goliaths, and Pulverizers guarding it. Destroy them and capture the Plant.
*Island Hopping: Get all of your naval forces to the central Shipyards. Have one build a Construction Ship. Then build Crusaders from one and Skeeters from the other. The third Shipyard should also build Skeeters and send them to the center. Build a line of Torpedo Launchers across the southwestern pass to the Shipyards and some more to the northwest. Focus fire is again helpful, and don’t forget your air force. Four Executioners and several Enforcers attempt to go through the northern pass to your Shipyards, so make sure your Conquerors are there to intercept. This is where your torpedo bombers are most useful. Two more Enforcers and a Missile Frigate follow them and two Snakes through the southwestern pass. They’re easy targets for your Torpedo Launchers.
*Mist Bombers: There are two large islands to the north, each with an Aircraft Plant and Kbot Lab. Find them and bomb them back to the stone age. Avoid unnecessary contact with AA weaponry.
*A Shortage of Water: Don’t worry about base construction. Take your starting units west to the edge of the map and then head due north. This gets around most of the enemy resistance, except for some lasers towers. There are two Gaat Guns on the way north, as well as enemy units and a Punisher. Destroy them before focusing on the Hydration Plant, which is northeast of the Punisher.
*Raid on Vetes: +shootall is useful. Just focus on the targets. Make exceptions for Cans and Gaat Guns. There are two Advanced Kbot Labs and one Fusion Plant. One Lab is in the northwest corner, the fusion is over to the east, and the last Lab is southeast of that.
*Three Passes: Send a light force over to the easternmost Moho. The enemy attacks in four waves. The first is two AKs to the center. The second is three to the west. The third is two Crashers and a Storm. The fourth and last waves is four Crashers.
*Spire Sports: Get two more Advanced Construction Kbots and build lots of Fidos. Your original Advanced Construction Kbot should build Mohos. Set up an Advanced Radar Tower two Annihilators, one near the Advanced Kbot Lab, the other to the northeast. The Construction Kbot should build a line of Sentinels in front of your base. Other than this, once you have a group of Fidos, just harass the incoming enemy. The only large push is at the end, when you should plenty of defenses.
ARM Medium: 10/10
*Lipar Pass: Build two solars and take your forces south. Blast through the Core line, focusing on Gaat Guns, and move to the south of the base. A bunch of Core trucks are here. Destroy them all. They move in circles, so if some escape, they’ll be back.
*Ice Base Assault: Take your forces to the western edge of the Core base. Rubbleize a section of four Dragon’s Teeth to make a path for your forces. Move your forces along the western edge of the base until you reach the top of the map, then head east. The fusion will be there.
*Pursuit: Move all of your forces to the two metal patches at the southwest end of your current view. Have your Construction Vehicles build Solar Collectors, Metal Extractors, and two Vehicle Plants. Build some radar towers as well. Have the Vehicle Plants build Flashes while the Construction Vehicles work on repair. Whenever you see enemy contacts, move your units to destroy them. Once you have many Flash tanks, sweep the northern border of the map, moving east. You should find and destroy all of Core’s remaining tanks.
*Backs to the Sea: A radar is your top priority here. The enemy is heavily concentrated in the southeast, with incredible numbers of units there. Repair your most powerful units and destroy the enemy units nearby. Being accurate with the D-gun helps tremendously. Be very careful, as there are large numbers of Goliath tanks. The Construction Vehicles are up and down the eastern edge, but check the southeast first. Be wary of a Gaat Gun in the area.
*Spider Ambush: This mission was very irritating for me. You can move out right away, so do so. There’s a large attack force not far from your base, so deal with that before proceeding. D-gun the enemy units. There’s a Gaat Gun and Goliath that must at least be stunned. The Advanced Construction Vehicle you must capture is in the northeast corner of the map. Just take your time and repair when possible. There’s an Advanced Construction Kbot running around, but ignore it, as it’s not your objective.
*Islands of Grace: Take your navy and bring it to the submarines. Then head south. Destroy the torpedo launchers and shore guards, including the rogue Zeus, before bringing in the Hulks. Only one seems to be loaded, so find it and unload it. Then send the units to the southwest corner where the Intimidator waits. My forces seemed to have destroyed the second automatically, as I never saw it.
*Wet and Dry: Take your entire navy north and destroy anything that gets in your path. Focus on Warlords. Destroy the shipyards at the center of the northern edge. There are units on an island to the west, along with another shipyard, so destroy that first. The central island, another to the southwest, and the northeast corner all harbor units. Destroy them all.
*Meraldi Amphibious Assault: Move your fleet to that one enemy contact on the radar. Have your factories build a Colossus and Skeeters. A group of Snakes will come by where that first enemy was. Use the radar provided by the Colossus to clear out the enemy defenses. Focus on the northern defenses and repair your damaged ships. Once the Tritons get moving, stop them until you’ve cleared a path for them. The Silencer is in the northeastern corner, guarded by a Gaat Gun and two Pulverizers. Once the Gaat Gun is down, taking out the Silencer should present no difficulty.
*Miniement Landing: First off, move your Skeeters near your Torpedo Launchers to give them line of sight. Move your Panthers and other units to the bridge connecting the island to the mainland. Then, start building Crusaders and get your Construction K-bot building a Vehicle Factory. Radar targeting helps tremendously. Use it. Use that vehicle factory to build Flash tanks. Remind the Core why these units were banned in net games and that they can still run circles around Goliaths. Other than that, focus fire and pick your targets wisely. You will lose many units, so don’t give up.
*Intimidator Ridge: You’ve got far more force than you need to break through. Charge! The Intimidators are on the northwestern hill, one on the southern edge, one on the west. Destroy both.
ARM Long: 5/5.
*Com Pattern Five: The trick is drawing in only one group of enemy units at a time. Use the Annihilators to hit the targets that are already in range at the start. When they’re gone, send out a single Fido with a Seer to provide radar. Hit units until you see a group moving. Then run back to the line and select your Annihilators. Manually fire them for best effect. Repeat as necessary. Other than that, have fun with this mission.
*Steel Stronghold: Simply put, you’re going to have pound wave after wave of units into the Core base. Harass them with Flashes and build Defenders about halfway between the bases. Get Brawlers out to help destroy the base. There’s really nothing for this mission but to keep pounding at the base.
*Thermal Exchange Causeway: Have your Commander build a Vehicle Plant, and then a bunch of metal extractors. Have your Shipyards build Construction Ships, and have those build Tidal Generators. Build an Aircraft Plant and then some Construction Planes. Build Crusaders at your Shipyards when you have enough metal income. Build several Advanced Construction Planes, Moho Extractors, Fusion Powerplants, and a bunch of Phoenixes and Brawlers. Pound wave after wave of units into the Core base. You’re going to lose a lot, so be prepared to send multiple waves. The Silencer is at the eastern edge of the map, in line with the southern metal hill. Once you have a clear path, destroy it.
*Crossing the Long Lakes: This is, as advertised, a long mission. Clear out your starting island but capture the fusion, a Core Advanced Construction Vehicle, the shipyard, and the Mohos. Build a navy consisting of Executioners and Searchers. Toss in a few Hives when you can. Build a Bertha firebase and shell the second island. Rapiers and Avengers will help clear it out. When the island is clear, start another firebase on the island. The tiny island in the southeast has the Gate on it, so scout your targets before you shoot. When that island is safe, bring your commander over and capture the Gate.
*Capture Hanan Base: The Core base is north and slightly west of your starting position. Set you forces to return fire, and clear out its defenders. Don’t use the D-gun, or you’ll run out of energy. Once the base is safe, take charge and capture as much Core infrastructure as possible. Build a Vehicle Plant, and four Construction Vehicle. Have the Core Advaced Kbot Lab produce Adv. Construction Kbots. Repair your starting units, and build Dragon’s Teeth and Defenders around your base. The Adv. Construction Kbots should build an Advanced Radar Tower and Mohos and Fusions as needed. Build Samsons and send them to the northeastern corner of your base. The first two enemy attacks, Goliaths and Pyros respectively, come from that direction. All others are from the west. Build an Arm Aircraft Plant, several Construction Aircraft, and an Advanced Aircraft Plant. Build Peepers and Avengers and have them patrol around your base. Several Core attacks are from Hurricanes, Shadows, Vamps, and Roach-carrying Valkyries. Hunter-killer teams of Brawlers and Eagle AWACS planes will help destroy the rest of the enemy units. They’re all to the west, so look there. Wait out the 40 minute timer if you finish early.