UFO Exit Ambush
While Sweeping the Battlescape, aliens will often remain inside the UFO. Inside the UFO, aliens have many places to hide, and your troops risk getting gunned down every time they stumble blindly into a room. It is therefore usually best to stake a position outside the UFO's outer doors and let the aliens come to you.
(TODO: picture of broken semicircle)
Lying in wait outside UFO doors for aliens is not without its dangers. Aliens may be able to fire at your troops (especially if more than one is waiting behind the door), or throw an Alien Grenade, or worst of all, fire a Blaster Bomb. If you arrange your troops facing each other on either side of the door, they may accidentally hit each other in a crossfire.
To keep from getting shot at by aliens hiding within the UFO when the door is open, avoid stationing troops directly opposite the door. To lessen the likelihood of a grenade attack, keep your troops spread at least two squares away from each other. And to avoid friendly fire, either keep all your troops to one side, or have them avoid positions near the UFO hull.
Once the surrounding area is cleared, keep pressing the "end turn" button. Most aliens will switch from "patrol" to "attack" after Turn 20 and will make a beeline for your troops, spilling out of the UFO. A few stragglers may take several turns more.
Unfortunately, some aliens may end up "frozen" in one spot, waiting for you to come to them. It may be possible to "dislodge" them by having each of your soldiers walk around the UFO. Howevever, sometimes they will not budge, at which point you will have to enter and clear the UFO. Large Scouts and Abducters are particularly prone to FAS: Frozen Alien Syndrome.
One way to reduce the likelihood of return fire is to drop a Smoke Grenade outside the door and station your soldiers 10-15 tiles away. Aliens emerging from the UFO will have to walk several squares before they will be able to see your troops, reducing their TUs subtantially, making it much more likely that your troops will be able to fire first. This also blocks the view of aliens inside the UFO, making it impossible for them to shoot at your troops from within the craft.
The smoke will thin substantially within 10 or fewer turns; a new Smoke Grenade should be triggered at least that often. The smoke from a Smoke Grenade is much thicker than the moke generated by explosives (Proximity Grenades, Rocket Launchers, etc.) and is much more effective in this role.
The best arrangement for your troops is in a broken semi-circle. Avoid stationing soldiers directly opposite each other on the left and right sides of the door, as they may catch each other in a crossfire. Also avoid placing troops directly in front of the door, as aliens may shoot at them from inside the craft once the door is open (unless you use a Smoke Grenade, as detailed above).
If possible, spread your troops out: troops which are standing shoulder-to-shoulder often attract an Alien Grenade. Flying Suits are excellent for UFO door ambushes: hovering troops are immune to grenades, and since they are firing downward, they can be placed on either side of the door, less likely to accidentally hit each other.
The soldiers assaulting this UFO have decided to wait for the aliens to come out. Four shooters are kneeling, facing the UFO's only exit. These soldiers have the highest reaction stats in the squad. It is recommend that only soldiers with good reactions should be used. However, the more soldiers the merrier no matter their reaction level, as every soldier that fires will get a chance of improving their reactions at the end of the mission.
The main benefit of having more soldiers is that they present more targets for the alien to shoot at. More importantly, every time the alien fires off an attack, this gives the slower soldiers a chance to react.
Before shooting one of the soldiers, an alien must:
- Open the door and step outside (8 TUs)
- Turn to face the target (2 TUs)
Or, if he's not the first one out:
- Move onto the square in front of the door (4 TUs)
- Step outside (8 TUs)
- Turn to face the target (2 TUs)
The total is at least 10 TUs. For slow aliens like Snakemen, that's a significant fraction of the total TUs, and the loss of 10 (or 14) TUs often allows a soldier to fire first. Also, aliens do not always start on the square next to the door so they may have used up even more TUs.
The other soldier in the frame isn't a shooter. He's a looter. Looters have nothing to do with increasing anybody's reaction stat and everything to do with increasing X-Com's "bank balance" stat. Looters pick up corpses, stunned aliens, and dropped equipment and carry them somewhere safe, where they won't get destroyed by an explosion. Stunned aliens can optionally be left alone to provide even more reaction training once they recover. The looter can also be used to scan the entryway for any possible movement during some of the more quiet turns.
If you're still nervous about your troops getting shot, put a tank nearby. HWP's draw fire; aliens prefer to shoot at them over troops. As long as the tank is in the aliens' line of sight, and as close or closer than the troops, the aliens will always shoot at it before the troops. When I train, I keep several tanks on hand, replacing damaged ones with fresh units as they get shot. --Papa Legba 14:09, 28 Nov 2005 (PST)
The square marked with a 'G' is a good place to put a Proximity Grenade. It is a good idea to mine the exit while the shooters are getting into position - in case an alien pops out before you are ready. Once the shooters are ready, the proximity grenade can be destroyed with a normal grenade. But if the UFO contains Mutons, leave the proximity grenade where it is to soften them up before the reaction shots. Then grab the loot and set another proximity grenade for the next one.
Note: Prox Mines do not give you any experience. More specifically - and oddly - unlike other grenades, they give experience to the unit that makes them explode, not the unit that primes or throws them. So, Experience that might've been gained is basically lost - newbie units (pre Power or Flying Suit) dare not set off their Prox Grenades (which is counter to their purpose), and PS/FS units generally have psi capability and don't need proxies any more. Sure wish they designed Prox Mines differently - Ed.
Which weapon to use?
This depends on how many shots you expect to get, which in turn depends on how many shooters there are, and how good their reactions are. If the number of shooters is small, it is best to use something accurate and powerful to get a quick kill. The Plasma Rifle has the most accurate snapshot in the game, and is an excellent reaction weapon. If there are lots of shooters with excellent reactions, spraying with rapid fire weapons like the Laser Pistol will result in greater stat increases. The Laser pistol is also incapable of penetrating the front armour of a Flying Suit or Power Armor, which makes it possible to set up shooters on both sides of an entrance without any risk of damage due to friendly fire.
- Note, fire teams that are directly facing each other should be avoided in general. I'll have to detail the scattered firing team approach at a later time - if only to avoid grenades. -NKF
Lack of an autoshot mode is not a disadvantage, because reaction shots are always snapshots. The Heavy Cannon may therefore be the best standard weapon for reaction shooting.
The Small Launcher
This weapon has the potential to generate many reaction shots - first to put the alien to sleep, and then every time it wakes up. This is bordering on an Exploit. But keep in mind that a stun bomb can do up to 180 stun damage, so it could take tons of medkits to wake up the unconscious target. Maybe it's not so hot a trick - but plenty of fun!
The Rocket Launcher
This is messy but effective. Few things are more entertaining than hitting an alien with multiple reaction-fired large rockets. If fired from some distance from the side of the UFO (e.g. by the blonde soldier in the picture) then even a miss is likely to strike the wall of the UFO and do some damage. Firing from above ground level - either with a flying suit or from the roof of a conveniently placed building - is also very likely to hit something close to the target. It is definitely not recommended when using two groups of shooters facing each other, and care must be taken to ensure that all soldiers are safely outside the blast radius.