TRTBAG

TFTD Research Tree Bug Avoidance Guide

by NKF

The designers of X-Com Terror From The Deep attempted to make the research process in TFTD much more complicated than its very straightforward predecessor's research tree. They have succeeded in doing this, but have also introduced many glaringly unacceptable errors in the process that can prevent you from completing the game.

Some players may have had the luck of not bumping into any of these errors by picking all the right research at the right time. Unfortunately, as the research order in TFTD is non-linear, that is to say you can research anything you've got in any order you want, a lot of us are less fortunate. This guide is to assist point out some of the stickier bits.

Until the content can be transcribed into wiki format, refer to the old version

---

Introduction

Unlike X-Com UFO with its fairly straightforward research tree, TFTD is rife with dead-ends that will prevent you from completing the game. This guide attempts to point out these problem and provide suggestions on how they can be avoided.

With the exception of MC technology, this document discusses a branch of the research tree that will take you from the very start of the game all the way to the final chamber in T'Leth. While this may spoil the game if you are new to it, it is better to be informed than to make a mistake that is irreversible. The game IS hard, even for X-Com UFO veterans.

This is not a reproduction of the research tree. There are many documents in a variety of formats describing the complete research tree on the Internet that you can peruse. This document is merely a supplement.

The word 'prerequisite' is used quite frequently throughout this document. As prerequisite is not an everyday word, here is its definition.

Pre-Requisite

Pre- means 'before'

Requisite means something that is required in order to achieve something.

In Layman terms and in context with the game, in order to get this thingy, you need to research or have these thingies first.

Research Order and Its Importance

Many of the problems in the game happen when researching certain items and aliens in the incorrect sequence. This normally occurs with alien interrogations.

As a rule of thumb, if an alien is a prerequisite for any particular tech item, it's highly recommended that you do not interrogate it until all the other necessary research items have been completed.

The Deep One Dilemma

The primary research path looks roughly like so: Armour, Subs and finally T'Leth

For Armour, it looks like so:

Deep One Corpse, Aqua Plastics, Plastic Aqua Armour, Ion Beam Accelerators, Live Deep One Terrorist, Ion Armour, Magnetic Navigation and finally Mag. Ion Armour

A Deep One Terrorist is the key to winning the game. You will need both a living specimen and a corpse. In older versions of the game, where you need a lobsterman navigator to get magnetic navigation, getting a live Deep One Terrorist is not that important. However, in TFTD versions with the V2 update, success hinges on getting a living Deep One terrorist.

Deep One Terrorists can be found in most Gill-man land missions. They rarely appear underwater*, and are replaced with Xarquids if you shoot down Gill-Men terror ships.

Don't worry if you missed them, Gill-Man terror sites do still appear when it's late in the game, although they are abundant early in game.

Deep One Terrorists also appear in 'mixed' alien crew land missions. A mixed crew is made up of a variety of species, and in terror sites and base attacks, will be supported by a variety of land-based terror units, which includes the Deep One Terrorist as well as the odd Xarquid (which normally replaces the Deep One Terrorist for underwater missions).

Just promote a terror site by leaving any ships on terror missions alone, or encourage the Gill-Men or 'mixed' crews to attack your base by shooting some of their USOs down near your base. You might also want to dismantle your M.C generator to improve the likelihood of an attack. .

Before starting research on the Deep One Terrorist, refer to the Ion Armour section.

Finally, researching an alien medic and getting information on the Deep One Terrorist or its corpse is not the same as researching the real thing. You will not get any research benefits from the alien medic's report. Keep this in mind.

• you can find some Deep One Terrorists in the

second level of T'Leth.

The Tasoth Commander

Whether this alien is a legal alien in the game is debateable. Nevertheless, do NOT make any attempt to capture this alien.

If you do capture it and for some reason it appears on your research roster, do NOT complete research on it.

Interrogating this alien will prevent you from getting critical research necessary to get to your final objective.

The only time it's safe to research this alien is after the "T'Leth" button appears on the Leviathan's intercept controls. But by then, researching it will just be redundant.

The MC Reader and Sub Construction

These two items, the MC Reader and the Sub Construction store item, are special in that they will only become available for research if and only if a sample is available in your general stores before completing research for their prerequisite technologies.

If you do not have any when completing research on the last of their required technologies, they will NOT appear later even after acquiring a few samples.

For example: If you've done Zrbite and are about to finish research on the Transmission Resolver, make sure that you have the 'sub construction' item in stores before the research on the Transmission Resolver hits 100%, or vice-versa.

Between the MC Reader and the Sub Construction store item, the 'sub construction' store item is required to win the game. The MC Reader is optional.

Note: This does not apply to Aqua Plastics. You can research it even without any samples.

Version differences

There are two versions of TFTD. The original unpatched version of TFTD and the one with the v2 update.

Players with the Collectors Edition of TFTD have the version with the v2 patch.

The known changes in the research tree are as follows:

Unpatched

A Lobsterman Navigator is needed to research Magnetic Navigation

Ion Armour is not required for Magnetic Ion Armour. All the technologies you need for Magnetic Ion Armour are Plastic Aqua Armour, Ion Beam Accelerators and Magnetic Navigation.

V2

Magnetic Navigation can be researched as soon as one is in storage. The lobsterman navigator is NOT required.

Ion Armour is required for Magnetic Ion Armour. Magnetic Ion Armour now just requires Magnetic Navigation and Ion Armour.

Yes, in other words, the V2 patch makes it easier to get Mag. Ion Armour. However, it also means that winning the game hinges on your ability to obtain a live Deep One terrorist AND researching it in the right order.

If you patch your game and reload a campaign created before the patch, you might face a few research problems. It's not that common, but you might find that you'll have some trouble with researching the more advanced armour via the V2 method. There should be no problems if you haven't even started on the Ion Armour or Mag Ion Armour yet. It's mostly for campaigns where you're already half-way through researching the armour.

The Good Bit

Armour

Plastic Aqua Armour

Prerequisites
Aqua Plastics

Notes:

Aqua Plastics are obtained from a Deep One corpse. You need not have any actual aqua-plastics in storage to get the Aqua Plastics research item.

Ion Armour
Prerequisites
Ion Beam Accelerators, Plastic Aqua Armour and a Deep One Terrorist
Notes:

Research the first two prerequisites in any order you wish. However, you MUST research the live Deep One Terrorist LAST. If you researched this alien earlier, you won't get Ion Armour. Capturing another Deep One Terrorist is possible, but there is a small chance that you will not be able to research any more of them.

This is especially important in versions of TFTD patched with the v2 update, as without Ion Armour, you cannot get Magnetic Ion Armour, which in turn is needed to get the advanced submarines.

Magnetic Ion Armour (TFTD v2)

Prerequisites
Ion Armour, Magnetic Navigation
Notes:

If you don't know what version of the game you have, the method in which you obtain Mag. Ion Armour will tell you which one it is.

For versions V2 and up, Magnetic Navigation becomes available the moment you have a sample in storage. Also keep in mind that Ion Armour is compulsory.

Magnetic Ion Armour (TFTD versions prior to the v2 patch) Prerequisites
Magnetic Navigation, Ion Beam Accelerators
Notes:

In older versions of TFTD, to get Magnetic Navigation, you need a Lobsterman Navigator. Keep in mind, Ion Armour is not compulsory.

Submarines

Manta
Prerequisites
Magnetic Ion Armour, Sub Construction
Notes:

Refer to the sub component section for notes on Sub Construction

Hammerhead
Prerequisites
Manta
Notes:

Leviathan
Prerequisites
Hammerhead, Lobsterman Commander
Notes:

The Lobsterman Commander should be researched after the Hammerhead. Also, for your convenience, don't forget to research 'alien origins' first so that you don't have to capture a third lobsterman commander to win the game.

If you did not research the commander and the hammerhead in the right order, don't worry, just research another Lobsterman Commander.

Tech to Win the Game

Alien Origins Prerequisites
Any live alien

Notes:

The Ultimate Threat Prerequisites
Alien Origins and a Lobsterman Commander
Notes:

Research the commander last. If you researched the commander before alien origins, don't worry. Just research another commander.

* A lobsterman Navigator can also substitute for the commander

T'Leth, the Alien's City Prerequisites
The Ultimate Threat and a Lobsterman Commander (another one) Notes:

You need to research another lobsterman commander.

If you researched the Tasoth commander any time in the past, then there's a possibility that this very important tech item will not appear, which means your current campaign has been scuttled and has already sunk all the way to the bottom of the ocean floor. Period.

If you don't have any saves made before completing research on the Tasoth commander, then your only recourse is to start a new game.

Molecular Control Technology (optional)

Optional because you don't need MC tech to win the game. But as its research branch has a notable bug, is included as well.

M.C.-LAB

Prerequisites
Live Deep One Terrorist OR live Calcinite Terrorist
Notes:

Either of the two terrorist units will give you the M.C.-Lab.

Deep One Terrorists generally follow Gill-men and Calcinites associate themselves with Aquatoids. Both aliens can be found in 'mixed' crew land missions.

MC Reader Prerequisites
MC Reader in storage, M.C.-Lab Notes:

The MC Reader research item will only become available if research on the M.C.-Lab is completed while an MC Reader is in storage.

If you miss out on this, you will NOT get the MC Disrupter or the MC Generator for the rest of the campaign.

MC Disruptor Prerequisites
MC Reader and any live Tasoth
Notes:

Excluding the Tasoth Commander, of course.

While the Ufopaedia says it only works underwater, this item will work on land. I believe the text was meant to say that only aquanauts with 'MC implants' can use it, the word 'underwater' seems like a typo that was never removed.

MC Generator Prerequisites
MC Disruptor
Notes:

This item will protect your base from being found, but it does not work 100% of the time. Aliens can still attack shielded bases if their scouts are lucky. The magnitude of USOs successfully spotting your base is reduced.

Alien Sub Components

Aqua Plastics Prerequisites
Deep One Terrorist corpse
Notes:

You don't need any aqua plastics to research it. You just need the Deep One corpse.

Ion Beam Accelerators Prerequisites
None
Notes:

Ion Beam Accelerator units are found in intact alien USOs. Most smaller enemy subs will lose their IBA units if shot down, although some of the IBA units may survive if they're in larger ships.

Magnetic Navigation Prerequisites
None (TFTDv2) or Lobsterman Navigator (pre-TFTDv2)
Notes:

In older versions of the game, a Lobsterman Navigator is required to get Magnetic Navigation. Otherwise, it should appear immediately on the research list once one is in storage.

Zrbite Prerequisites
None Notes:

A clump of Zrbite can be found underneath an Ion Beam Accelerator unit. If any explosive detonations occur near the IBA unit, it will be destroyed as it is very brittle (or rather, the IBA will blow up).

You can pick up these clumps, but finding a clump only occurs in unusual circumstances. For example, throwing an unconscious soldier into an IBA and waiting for him or her to wake up. Falling down onto one or walking into one with the walk-through-walls bug.

Xcomutil users will often find Zrbite clumps lying about when selecting a USO floor map that is not the same as the type of USO you're actually attacking.

Sub Construction Prerequisites
Sub Construction(store item), Zrbite, Transmission Resolver
Notes:

Keep at least one 'sub construction' component in storage before completing either of the two prerequisites. If you don't have one when both the prerequisites have been met, you will not get the 'sub construction' tech item, which is required for the advanced submarines

Transmission Resolver Prerequisites
Magnetic Navigation
Notes:

Obligatory Disclaimer Claptrap:

This document will not always be 100% accurate, as the game tends to behave differently for different players with different computer systems and game editions.

These notes are derived through many controlled tests and observations with the MS-DOS edition of Terror From The Deep with the TFTDv2 patch. Any noticeable difference between the patched game and the older versions are noted. Otherwise, these notes are valid for practically any version of TFTD available on the PC, with the possible exception of TFTD for the Sony Playstation.

TFTD, Terror From The Deep, X-Com, XCOM, et. al. originally developed by some very fine people. Originally distributed by Microprose. Now? Who knows.

As the purpose of this document is to inform, feel free to distribute any information in this document as you see fit.

Many thanks for the input and feedback from the regular posters on the Xcommand and X-Com Tactical Command forums for assisting in the preparation of this document. Some indirect thanks to the fine folks on the alt.games.x-com Usenet newsgroup as well. Extra bits and pieces here and there picked up from the xcomufo.com forums as well.