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Ground combat general tactics:
1. You will start in your drop ship, depending on the mission (Crash site, landed ship, terror mission, alien base) the aliens will be scattered across the map. They could spawn right outside your door.
2. Different missions will have different aliens, so arm your men to deal with them all.
3. Different missions will have different environments. Arm your men accordingly. When you click on a crash site it will tell you if it is a desert, urban, ex and its size. NOTE that tanks do better in open ground then in urban cities. There will not always be a path for the tank to get to the UFO.
4. Apart from base defenses, It will always be your turn first, so take advantage and secure the perimeter of your drop ship.
5. When storming a UFO, keeping the front door in one piece is a key tactic. You can use one soldier to open the door, the rest fire at the aliens, then you shut it. Now the aliens have to open the door and open themselves to reflexive fire, or they just sit there and move around the UFO.
6. LMGs are good for killing, but great for keeping aliens suppressed. When they are suppressed, sometimes they don’t move. Use this tactic in unison with tip #4 and you will have an advantage.
7. Take your time getting to the UFO. Don’t rush or you could be ambushed.
8. Keep your men in cover, crouched and watching all directions, you don’t always know where the enemy is.
9. Don’t always use all your TU, it helps with reflexive fire.
10. Make sure all your troops get kills, this means the experience is spread out among your soldiers so you can have more people level up.
11. Use the equipment you have, if you have grenades, pistols, shields, use them!
12. Don’t spread your men out across the map in the first few turns, advance in groups, so that when people get inured, you can heal then, cover them, or save them.
13. When going on a terror mission, civilians sometimes run to the drop ship and hang out in it, so keep it clear of aliens.
14. Advance in perimeter, try not to leave gaps where aliens could slip behind you.
15. Tanks are cover that can shoot, but be careful that they don’t explode for they will kill your men.
16. Grenades your men throw will sometimes not move from the square they are standing in, so be sure they have TU to escape the blast radius.
17. Higher ranking aliens love grenades, keep your men spread apart so that they can grenade less of your people at once.
18. Predator armor wearers are like a mule, they can’t use small equipment, but they can carry small equipment for the team.
19. You can make your own classes, make sure you have a medic. It is also a good idea for at least 4 of your soldiers to carry med packs.
20. Put your people with the best armor through teleporters first to scout, then come right back.
21. Gassing rooms with aliens in them help's taking them out, for gas covers a large space and it limits where aliens can go without being hurt or stunned.
22. Place snipers on roofs, they will have an advantage.
23. If your troops are all dying, you can retreat back to the drop ship, and get who is left out of there. You will fail the mission however.
24. Have backup, your men will miss.
25. Aliens have reaction fire, so be careful when advancing towards one.
26. When your audio is on, you can hear battle and noises in the distance during alien turns. Use this to determine the type of aliens you are dealing with. This is especially important when reapers are on the map.
1. Everything above applies to night missions.
2. When landing at night, take extreme care, you will have a sight disadvantage for your men.
3. Aliens are not affected by night missions, and neither are vehicles, for they have headlights.
4. Flares are infinite, so use them, they will take TU to throw but they give you an idea of what is out there.
5. Flares expire, so make sure you replace them if needed.