Talk:Alien Appearance Ratios (TFTD)

In these tables there is only one column for "Mixed Crew", but there are two different sorts of Mixed Crew. What's going on here? Magic9mushroom 07:34, 7 February 2012 (EST)

That's because there's only one column of probabilities available in the table that is taken directly from the game executable. I think where the mixed crew types 1 and 2 come from is the equipment and rank makeup tables. NKF 01:08, 8 February 2012 (EST)

So a single Alien Surface Attacks mission with a Mixed Crew (according to this table, the only Mixed Crew mission that should ever occur) could have different (ie Tasoth-based vs. Lobsterman-based) crews on different subs? This sounds like it needs to be checked. Magic9mushroom 02:35, 8 February 2012 (EST)

I had a re-read of the relevant articles, and I see the game specifically marks them as a type 4 and type 5, yet the probability table only has one column for both. If this is the case, then the game must do a toss between the two main races at the time it decides on creating the surface attack scouting wave or instant surface attack mission. NKF 02:52, 8 February 2012 (EST)

The choice between the two types of Mixed Crew appears to be not the only one the game makes. Tasoths on land missions can be accompanied by either Bio-Drones or Triscenes (not by both). I have saved a game just before a Shipping Lane Attack mission, and tried to start playing from it several times. And I have always got Tasoths + Bio-Drones on a Cargo Ship Terror mission. So, the "racial" contents of the alien crew as well as the type of the attacked ship must be fixed before the start of the mission. The only thing that changes is the number of the aliens.

As a result, in the observed alien appearance ratios some sub-types are distinguished:

1. Tasoths on land missions

 (a) Tasoths + Bio-Drones
 (b) Tasoths + Triscenes

2. Mixed Crew on land missions

2.1.
 (a) Tasoths + Bio-drones + Aquatoids + Xarquids (or Calcinites?)
 (b) Tasoths + Triscenes + Aquatoids + Calcinites (or Xarquids?)
2.2.
 (c) Lobster Men + Bio-Drones (or Calcinites???) + Aquatoids + Deep Ones

(Details on Mixed Crew are quite a mystery for me; here I am relying on the contents of Mixed Crew article rather than on my own observations from the game.)

Do you know how and where the sub-types are coded in the game exe or/and data files?

Sherlock 09:12, 19 January 2013 (EST)

Addition: if to believe what has been said in Talk:Mixed_Crew, Bio-drones and Triscenes are possible in one mission side by side - only with the mixed crew of Tasoths and Aquatoids? Telling the truth, I have not spot one yet (even if played TFTD many times). Any way,

Tasoths + Triscenes + Bio-Drones + Aquatoids + Calcinites on the 1st stage

Tasoths + Triscenes + Bio-Drones + Aquatoids + Xarquids on the 2nd stage

of a ship terror mission have been reported.

Perhaps yet more types of Mixed Crew are possible then. It is hard for me to check it: mixed crew may not happen is some campaigns at all.

Sherlock 09:49, 19 January 2013 (EST)

a) Sonic research encouraging tougher aliens b) Tasoth appearance time error?

I've seen this referred to elsewhere, but I can't find it now: someone wanting to "bust the myth" that lobstermen appear later if you delay research on sonics. I'm just playing a superhuman game, and have researched all sonics pretty much as late as possible, and lobsters haven't appeared until June. It definitely feels like a very late showing, and it came just after I got my first few sonics.

I had the same occur in UFO with late appearing snakemen (& mutons and ethereals) when I delayed plasma research.

If the new appearance percentages come in on the 1st of every other month, and don't ramp up gradually, then this data supports the tentative theory for me: it has been quite marked. How well understood is the code about this?

As a second, related point, something appears to be wrong somewhere with these charts: Playing TFTD on steam, with Xcomutil being used to catch bugs and having an otherwise "classic" game, I had a Tasoth and Bio-drone cargo ship terror mission on May 1st, which should be flat-out impossible according to these tables. It's now June 16th and I still haven't seen them since.

Even though the aliens start to get the probability of appearing, that doesn't always guarantee that they'll appear. I had one game in UFO where I never even met the Mutons. Once they get a probability of appearing, missions for these races will start to get scheduled from the 1st and will not necessarily show up right away. What you'll get initially will be the leftovers from the last month.

I'm not sure about the slightly earlier Tasoth mission, unless these probabilities only affect the normal sub waves that go out searching for a terror site and the monthly instant terror missions follow slightly different rules (Or suffer a fencepost error). XComutil doesn't touch the probabilities, and I doubt the probabilities will have changed when the Dos version was ported to the CE version. -NKF 03:55, 19 June 2012 (EDT)

Tasoths + Bio-Drone shipping route attacks in May may be a rule in the game, or an result of a bug. I have just got one as well. And I have checked missions.dat - there is no trace of any Tasoth activity there, only 0 (Aquatoids) and 1 (Gill Men) missions. Which is more, there is not a single Alien Surface Attack active mission recorded in there as well. I have checked saved games before the attack (of April 2040) and after the mission, and still no trace of any Tasoth alien mission at all.

In addition: the place of the attack is not very far from a base of mine. There is a Wide Array Sonar in the base, so the chance of detecting a battleship heading for the attack was not very low - but I did not detect anything, and such an event is not the first time. It looks like the aliens emerged from beneath the waves just to the attacked ship.

Some interesting questions arise then:

(1) Shouldn't any alien active mission be recorded in missions.dat?

(2) Is there a possibility that some kind of alien activities are hard recorded (in the exe) and are thus basic events of the game timeline (or its milestones)?

(3) Or perhaps the-first-day-of-the-month alien surface attacks are not scheduled in the same way like other alien missions?

And, as a consequence, tasoths may appear on them even if they should not have appeared yet, as it is too early for it according to the game alien appearance ratios?

Sherlock 09:35, 19 January 2013 (EST)

I'll just chip in and say I've seen a Tasoth shipping route terror mission as early as 1st April (it wasn't an April fools, sadly). In fact, in that game they showed up before the Lobster Men. I was playing on Superhuman. --Darkpast 10:32, 30 July 2013 (EDT)

Update: I think I may have found the answer to the Tasoth mission in April. According to the tables here, it seems that a Lobsterman terror mission has a 50% chance of spawning in April. However, I remember that every single time I played the game, there was a Shipping Route mission with either Lobster Men or (rarely) Tasoths in the first few days of April. Therefore, Sherlock's point #3 seems correct: the missions at the beginning of the month are recorded somewhere else... And I have a hunch it's the same place that Artifact Site missions are recorded, because Artifact Sites aren't "normal" missions either; they simply pop out of nowhere. Furthermore, later in the game there will (almost?) always be either an Artifact Site or Shipping Route mission at the beginning of the month - if you try re-loading the game you'll see they're interchangeable; you can get either one (seems the chance is 50-50). --Darkpast (talk) 17:22, 3 July 2014 (EDT)

Alien Missions and Attacks

Perhaps I have found a solution of the April Tasoth problem, and by the way, of the problem of alien appearance ratios for Floating Base Attack, said to be superfluous and not used by the game.

It seems that the aliens take a part in both missions and attacks which are not part of any mission (and thus are not recorded). Single attacks (not being part of a mission) mean shipping route, port and island terror attacks, not scheduled before, not preceded by an appearance of any USO (the aliens attack immediately) and not in agreement with the tables presented in the current article. Hence Tasoths may appear in April, and hence aliens may terrorize land as early as in the first days of the campaign.

Note that an Alien Surface Attacks mission, unlike a single attack, contains of several phases. It begins from smaller USOs, and only in the last phase a Battleship appears and attacks a ship, a port or an island. It is in total agreement with the appearence charts discussed here. Unlike this, single attacks are not preceded by smaller USO's, and are not in agreement with the charts.

Single terror attacks are frequent in first months, then they seem to cease. Aliens can still terrorize ships, ports and islands but during their Alien Surface Attacks missions rather than single attacks.

As it seems to me, a similar mechanism lies behind attacks on XCom bases. Some of the attacks are a result of an alien response to downing a USO (with a chance which depends on the game difficulty level). Contrary to single terror attacks, a Dreadnought always appears then. The aliens know exactly where the XCom base is located. Appearance ratios are of no use then - it is the same race which responds, as the race whose USO was downed by XCom.

These single attacks in response to USO downing seem to have nothing to do with Floating Base Attack missions. Like other of the 7 mission types altogether, Floating Base Attacks are scheduled and consist of several phases. Alien Appearence Ratios are applied. It is only a chance that the aliens will find the XCom base location.

Sherlock (talk) 07:40, 14 September 2014 (EDT)

You would be right there. The tables only really apply to the scheduling of UFOs that show up in chained scouting waves. The more regular appearances. The one-offs are a bit of an exception.

I don't recall getting into this situation myself, but if the aliens were persistent enough to create a colony very early into the game, and you were eager enough to tackle it with the good old harpoons and gauss, then you would quite likely meet the Tasoth well before they are scheduled to start appearing. NKF (talk) 01:39, 15 September 2014 (EDT)

I've noticed this discussion on the OpenXCom forums about the Single Attacks, as called by Sherlock and my question here is what proof there is (code/setting in the game files, etc.) that they exist and if this isn't a misinterpretation of the UFO wave system. NKF already mentioned that Tasoths can appear in the early game if the RNG spawns an alien colony in the first months, or if an Artifact Site is activated, although the latter only appears after a certain game stage IIRC. So let's take a few of the claims here and try to examine them in the light of the current theory.

• "It seems that the aliens take a part in both missions and attacks which are not part of any mission (and thus are not recorded)." - by not being recorded I assume that it means that it doesn't appear on the graphs. But what is the point of not recording the attacks, since they will not score points for the aliens?
• "Single terror attacks are frequent in first months, then they seem to cease." - Could this be that in the first months the sonars don't automatically detect all the UFOs (only the Transmission Resolver does so), so they have failed to pick any UFO scouts send as a wave?

All this being said, it is quite possible that some missions (Artifact Site) don't have any scout UFOs being generated (or simply any UFOs) but to me the real proof lies on the MISSIONS.DAT equivalent of TFTD rather than ingame observations that might be flawed. Warboy1982 should be checking this for OpenTFTD so we should have some light after he finishes the conversion. Hobbes (talk) 10:01, 15 September 2014 (EDT)

To settle the confusion over this, i've made a small adjustment to the tables to reflect what actually happens in the function that spawns the shipping route missions. It doesn't take the progression of time into account, it simply references the fourth racial distribution table for alien surface attacks. In short: tasoth shipping route terror missions are a very real possibility, even as early as april 1st (as supported by all the anecdotal evidence above) --Warboy1982 (talk) 09:29, 30 August 2015 (EDT)