Talk:Base Defense (TFTD)

For TFTD Base Defence missions, there is mention in some articles that the spawn points are different, that aliens will routinely appear in places other than the Airlock and Sub Pens (not just if the aliens run out of their own spawn points).

From personal experience (one Base Defence so far!), the spawn points do appear to be different, it looks like perhaps some of the aliens can spawn in adjacent modules to the usual spawn points, while most of them spawn in the usual modules. Or did I read somewhere that they start in the normal modules but get 1-2 turns free movement? I don't think so, as I had 2-3 aliens who were nearly the whole way on the right hand side of the base, when the access lift "channel" on the extreme left side of the base. So I think they teleport/leak through into adjacent modules to the sub pens and access lifts.

Still, the overwhelming majority of aliens were in the normal spawn points - sub pens and access lift - so a few leaking behind the lines does not invalidate the overall Base Defence strategy.

I think it's the module adjacent to the airlock or sub pens. One way would be to ensure that the sub pens and airlock are separated from the rest of the base with the good old one-chokepoint base strategy for the primary base. Perhaps with a slightly longer chokepoint.

For smaller sonar/intercept outpost, just throw everything down at random. With aquanauts appearing from all directions, spawning one module along means little. On the bright side, f the aliens start closer, the better the opportunity to use the power tools!

One thing to check is that this isn't a result of having too few alien spawn points. It's very unlikely as I've had a 3 sub pen base have aliens start in adjacent modules, but you never know. Really small one-or-no-sub-pen bases tend to suffer from this. -NKF 00:45, 10 October 2008 (CDT)

I once had a commander witha small launcher spawn near a general stores. Thank goodness my Gas Cannon tank was next door and drove right in front of him, with lead to the commander to stun himself. I had a fairly stable base going, all Sub Pens using the top two rows, one access lift in the third, and all other buildings in rows four throught six. He (the HQ) showed up around the eigth turn, long after I had barricaded the choke point. Muton commander 21:52, 11 October 2008 (CDT)

Not sure what all this talk about "adjacent" modules was about, so I decided to take a look at the TFTD X-COM base spawn points to see what I could find. First some background on Enemy Unknown X-COM base spawn points (this is where I did most of my original testing on spawn points). There are 3 categories of spawn points: X-COM units, Shared, and Alien. Ignoring the HWP's for this discussion, X-COM soldiers are the first living units to spawn on a map. They will always be placed in X-COM flagged spawn points first. If they manage to fill those up, they start to fill the shared nodes. Finally, if the shared nodes are filled, then X-COM units will start spawning in the alien flagged spawn points. After the X-COM units have been placed on the map, then the alien units get a chance: first in the alien flagged nodes, then in shared. (I'm not sure whether alien units can spawn in X-COM flagged nodes, I don't think they can though). Aliens can only show up in the access lift and hangars first, then the shared nodes (which consist of most of the facilities in the game). The modules where only X-COM units can start is the LQ's and Lab. The General Stores is also one of these but it has a single bugged spawn point which is shared for some reason. There are 3 more facilities with X-COM points but also shared points: Workshop, Large Radar and Missile Defenses. That's for Enemy Unknown.

In TFTD, it's totally different. For the most part, the map programmers didn't utilize shared spawn points anymore. They only have X-COM and alien. The aliens mostly show up in the Air Lock and the Sub Pens like in EU, but X-COM units now occupy all the other modules in your base. This is generally speaking of course, there are some obvious exceptions as you guys have noticed. Here's where there is a problem: the Living Quarters have 3 alien flagged spawn points with a spawn priority of 1 and the Bombardment Shield has a single alien flagged node with a spawn priority of 4. (The Torpedo Defenses, Alien Containment and Sonic Defenses all have one node which is shared).

Let's take a look at the alien controlled modules a little closer. The Access lift in EU has 8 alien nodes while the Air Lock in TFTD has 9, so there isn't much difference here. However, in EU there were 15 alien spawn points in each hangar, but in TFTD there are only 13. If the base defense mission doesn't have any flying units, then the Sub Pen only has 9 alien spawn points. This is a significant reduction in the number of available nodes for the aliens. Once these locations are filled (they are high-priority so they fill fast), then aliens may start to show up in those other locations (most likely the Bombardment Shield first as it has a priority node of 4 and then the LQ's).

The alien flagged spawn points in the Living Quarters and Bombardment Shield are most likely unintentional errors by the map programmers. So are those shared spawn points in the Torpedo Defenses, Alien Containment and Sonic Defenses. That's my guess. Those nodes are probably meant to only hold X-COM units. I say this because the routes in the TFTD X-COM base modules are literally a total mess. In some of the modules the routes are in a state of total disarray. It almost looks like the map programmers didn't quite finish the job. Makes sense, as from what I've read, they had a hard time figuring out the routes utility written by Julian Gollop for EU. --Zombie 12:44, 10 October 2008 (CDT)

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Some more points about TFTD Base Defence missions: underwater-only weapons (HJ Cannon, Torp launchers, etc) are automatically excluded from your 80 item limit, so you don't need to sell/transfer them. This was a help for me because a battleship hit me with no warning (near end of February on Superhuman). I did not get anything on sonar (long range and short range). Possibly it was because I had time advance set to 1 Hr, but you would still expect to get a popup box and for the clock to stop when the incoming battleship is detected. No such luck for me.

They still show up as items that you can equip, as I've had cases where the remainder of my Aquanauts had nothing else to arm but some hydrojet cannons. They can be fired with reaction fire, but being one of the slower snap weapons and the fact the TFTD aliens seem less inclined to rove about as much as their UFO cousins, the HJC's don't inspire very much confidence.

A general land based feature that you can enjoy during base defence is improved phosphor performance and explosions appear to be much more destructive to terrain featues. At the very least you'll get the skull flames instead of bubbles. Not strictly exclusive to base defense, but worth knowing. -NKF 00:45, 10 October 2008 (CDT)

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Fair point NKF, let's continue the discussion over here! A lot of the other TFTD articles are also a bit raw/chatty so I thought it would be ok. Also as there is a dearth of TFTD articles I thought an article, albeit a chatty one, is better than no article at all and a Talk page. I suspect casual users tend not to look at the discussion pages much (I'm talking about a hypothetical "layperson" not the site's regulars!). But mainly to be honest I'm not qualified to write a proper summary, so I thought if I started a discussion people like your good self might chime in with help - as you have done, so thank you!

Anyhoo.... Yes the base I had was 3 sub pens at the top 2 rows, airlock hard left on row 3, then the rest of the base starting at row 4. Aliens were found on combat turn 1 on the middle and mid-right of row 4. They were just Gillmen and Deep Ones, which I don't think are that fast?

My heaps of HJ cannon and torps were not available to equip, just loads of gauss weapons and clips and my one and only gas cannon. Initially I thought maybe TFTD is different and denies you the (best) weapons from your transport(s), so I was fighting with my surplus gauss production. Is that possible?

Or do gauss weapons sort higher than HJC on Torp launchers on the 80 item list? I didn't think that they did. Or maybe it's an (undocumented) XComUtil feature. Perhaps XcomUtil removed them from the equip screen but all the HJCs were lying around upstairs on the floor. I will have to see if I have a save of that game.

Thanks for the tips on HE and P shells, that's a good one.

I'm still surprised that I got absolutely no warning of the impending attack, nothing until the Base Defence mission screen came up. Anyone got any ideas about that? Is it normal? Spike 03:49, 10 October 2008 (CDT)

I was going through some of the TFTD sections this evening, and man do we need to perform a serious overhaul. The alien descriptions would be a good place to start. For this section, maybe just a pointer to the talk page for now would do.

The Gauss weapons are actually further down the list than the torpedo launcher and hydro jet cannon. But then again, so are the sonic weapons. In the few games I've been playing recently, I've noticed that sonic weapons get selected before all of the basic equipment. I think the game re-orders the sonic weapons and gauss weapons to put them before the others, much like how they re-ordered the weapon list in UFO so that the three pistols were always picked last.

As for the base attack - it can happen. Your sonar arrays do a ping at every 30 minute interval to reveal any USOs flying in range. If the Dreadnaught slipped through into your base during the gap between the sonar pings, then you would not have seen it. The scary thing is that this can happen even with a Transmission Resolver! -NKF 06:48, 10 October 2008 (CDT)

Ah thanks for the explanation of "surprise attack". That makes sense and maybe is worth noting under the main Base Defence article which generally assumes you have some prior warning. On the 80 item limit, more investigation needed, but it looks like the developers were trying to workaround the bug. I wonder if they just reversed the sort order, to put the more advanced weapons/items first? Simple and fairly effective. Spike 09:15, 10 October 2008 (CDT)

NKF, I'm not sure it's possible for a Dreadnought to fly in under the radar of a Transmission Resolver. A Dreadnought can't move faster than 4800 knots - 4800 nautical miles per hour - and the Transmission Resolver has a range of 2400 nm and checks once per half-hour. Magic9mushroom (talk) 10:42, 18 December 2019 (CET)

Aliens with underwater only weapons

After many many years I went back to play TFTD (using OpenXCom Extended) and I noticed that many of the aliens attacking my bases are carrying DLPs, which are underwater-only. Is this something that happened in the original game, or is it related to OpenXCom? If this can be confirmed, it should be worth including in the article. Diegoba 11:48, 8 June 2023