I was wondering the same thing, so to help everyone out I went through all the missions again to find out.
The Signal- 04:00
A New Enemy- 20:00 I got it in 13:40 on normal with After Party on, just move as fast as you can to the first base and immediately push to the second with whatever’s left. Build the base, but cancel it before it’s built for a free scorpion and Marine squad. Do this a few times and your pop will go over 80, then just push everything to the boss fight.
Ascension- 20:00 I recommend using bountiful harvest Skull and sugar cookies, then spam tf out of air. Put Jerome in a hornet if you like, but I had the easies time With 3 Marines and nothing but hornets.
130- 10:00 Have Alice break out all the prisoners and have them grab supplies and power while she continues. In the main defence I put the cyclops in the posts, Alice mid for the first two waves then right for the rest, hogs left. I kept the Hellbringers mid, but you can put them wherever you want pretty much. I did it on normal and got 10:08, so if you run easy for it you should have no troubles
The Cartographer- 30:00 This ones easy af. Do the After Party thing again, if you want you can send in 2 or 3 tanks on the very first objective while you keep building pop, but you don’t need to. Start building up the base when you get that sweet 86 pop and just rush everything with your 5 tanks and -Yoink- ton of Marines. As for your base, I just did all pads and generators. Once that’s done, all units that -Yoink- back to base and to the end of the mission. Focus fire on the protectors if you want, but it doesn’t matter too much. I finished it in 16:21 like this, so it works pretty well.
Lights Out- 30:00 Once you get to the first base, recycle it twice for them units, then make nothing but pads, generators, and an armory to increase pop. Immediately push through the portal when you start actually building up the base. I left 4 Marines to deal with banshees until turrets were up. Take the minibases, but don’t forget they’ll both drop a wraith. After party spam one of them and throw a marine squad or two in the tower to keep eyes on the plot if you lose troops. All units that -Yoink- through the teleporter, then wait a few seconds. There’ll be a bombardment, so just put them back through to the minibases while that’s going. A relatively small force of banished will also be coming towards the minibases, kill em if you want, then teleport. Make a base if you want, but you won’t need it. Push to there’s and take it out, but have your hornets go straight to the teleporters control thing just passed the base. After party spam if you need to, and head over to the boss fight.
I’m posting it now, I’ll edit the rest of the missions in as I go.
From the Deep- 20:00 This one is wack. Kill the first wave as fast as you can and, as always, After Party spam the minibase. Every wave comes a set time after the previous, so the only thing you can do to speed it up is kill the first wave faster and kill the scarab faster. After the first wave is down, send a marine to each of the forerunner power generators and build up your base. I did 3 pads, 3 generators, and an armory to bump pop. In the marsh area to the right I had two garrisoned Marines and a scorpion, in the middle I had an anti air turret, the wolverine from the beach, and two cyclops in the garrison. Everything else was on the beach. Doing this you shouldn’t have any problems, also I’d recommend upgrading your vehicles and infantry. As soon as it says primary objective complete, all units to the beach for the scarab. Make sure you have all units attack the scarab so none of them are in the back doing nothing. I didn’t and got 20:24 because of it.
Hold the Line- 31:35 just win and you’re good.
Under the Dark- 25:00 First off you have to kill a bunch of guys with snipers. You can drop in ODSTs if you want to make it a bit faster. When you get the minibase, After Party spam, but make sure your snipers are in the corner so they have view of the enemy base. By the time you get all your guys down there, it’ll be shields down. On the switch to Alice, same thing, but I’d recommend not blowing the portal generator until you have bout 2 scorpions. Drop an ODST squad if you want the generator captures to be faster, but you don’t have to. Anyways, straight out the base I had scorpions go right and Marines with 1 scorpion left. Make sure 1 Marine squad goes right to cap the generator. Have the kodiaks trail behind a bit, and leave some guys to protect each one. Make sure you drop an armory and research reinforcements by the time you get to the next minibase so you can get more guys. Also note that if you forget to move kodiaks up and you have pop to spare, you can drop ODSTs on the other side of the barriers to knock them out.
The Foundry- 22:00 You can drop ODSTs on the way to the scarab, and it does speed that up. I dropped em twice and had a cyclops grab supplies so I could heal. Once you get a base, immediately throw down some pads and generators. Send your scarab left with a squad of Marines/ODSTs, there are power nodes and a minibase. As always, After Party spam. Build an armory to increase pop when you can. Just push and keep recycling those minibases till the job is done.
The Halo- 20:00 This one is hella easy. As soon as you repel the sentinel, send all your units to bravo base. Once you have it, take the minibase and spam that After Party. Send you 3 Spartans to C, Jerome and Douglas in the garrisons. 2 scorpions, 3 Marines, and 3 ODSTs are more than enough for A (upgrade Marines to combat techs), and put everyone else on B. I left a hog on the empty minibase in case anything died. Upgrade techs if you get bored.
Last Stand- 23:00 Just play through it and that’s what you should get. You might as well just play for score or on Legendary
Gatecrashers- 45:00 Again, After Party spam. Grab power nodes. Get yourself max pop as always, and massacre a base. While building up your own. I built 2 pads/generators, an armory, barracks, and garage. Roll on to the next base, and once it’s out banished attacks are mostly done. There are a couple minibases and some banished around various points.
Not on my Watch- 45:00 This one is easy af, I got it in time when playing for score. You can After Party spam if you’d like but I just did 12 Mantis and a bunch of Marines to fixe everything.
