Two Part Missions

Information

Two part missions are missions where two missions are strung together in sequence. They are long and dangerous missions by nature and test the endurance of many commanders as there are no breaks between each mission for troops to rest up from their injuries or rearm. They must also complete the mission with what remaining ammo they have on hand or what they've managed to pick up during the battle.

In X-COM Enemy Unknown, the only two-part mission is the final mission, Cydonia.

In Terror From The Deep, two-part missions include the Shipping Lane Mission, Artefact Site and Colony Assault. Terror From The Deep also has one three-part mission for its final mission: T'leth.

Mission Structure

Multi part missions involve two (or three) maps that are chained together that are played in sequence.

When the first map is cleared by meeting one of two conditions, the second map loads and must then be cleared by meeting its particular set of conditions.

First Map Clear Conditions

In all cases, the first map can be cleared by:

1. Aborting with troops standing in the designated exit area ¹
2. Clearing all aliens on the map.

When aborting with troops in the exit, only these troops will carry over to the next map. This allows you to end the first part of the mission earlier and ignore all remaining aliens on the map. The limitation to this method is the number of troops and perhaps tanks that can be carried to the next part.

The second option allows you to bring every unit that is still alive to the next part. In Terror From the Deep, there is also the prospect of equipment recovery depending on what version patch has been applied. See below for more information.

¹: Shipping lane mission differ slightly and do not have an exit area. All aliens must be cleared to progress to the next map.

Second Map Clear Conditions

In many cases, the second map is cleared by:

1. Destroying the mission objective and aborting with troops in exit area. ¹
2. Clearing all aliens on the map. ²

As with the first part, the advantages of either method are very similar.

Clearing the mission objective and aborting with troops in the exit area allow the map to be cleared faster. You risk losing recoverable equipment and mission points this way, but this is desirable if the mission has not been progressing in your favour.

There is no benefit to clearing all enemies in the second part of X-COM Enemy Unknown's only multi-part mission. In Terror From The Deep, clearing all aliens on the map allows everything that is recoverable on the second level to be recovered. For information of equipment recovered in the first part, see below for the specifics.

Note: If you lose all of your aquanauts in the second map or abort without any aquanauts in the exit area, any aquanauts left behind in the first map and the transport will be lost.

¹: The objective in TFTD's shipping lane mission is to clear all aliens on the map.

²: In the case of the final mission, the main objective must be destroyed.

Aborting

Aborting is used in two ways in a multi-part mission. The most obvious reason is to concede defeat and simply abandon the mission.

The second use occurs when troops are standing in the designated exit areas. In the first part this allows progress to the second map, with only the troops in the 'entry points' progressing to the next part. Troops that are not inside the sub or the entry point will be treated as if they were left in the sub.

In the second map, it allows you to leave the map early, with only the troops in the exit area. The victory condition of this action depends on whether you have met the mission objective or otherwise.

Aborting in any segment in Enemy Unknown without meeting any of the victory requirements means instant loss of the entire game.

Equipment Recovery in X-COM

In X-COM Enemy Unknown, as the only two-part mission is the final mission, recovery of equipment left on the ground or in the Avenger is irrelevant. Only equipment carried by soldiers that manage to get to the next map will bring their equipment with them. Therefore, if you plan to bring any particular weapons or tools with you, make sure they are carried as there is no going back (in a manner of speaking).

Equipment Recovery in TFTD

In Terror From The Deep, equipment recovery differs between the TFTD v1.0 and TFTD v2.0 or greater.

TFTD V1.0

Most copies of the Dos version of Terror From The Deep installed directly from floppy diskettes or via the original run of CD versions will default to v1.0. In this version all equipment that is not carried by aquanauts will be lost. Equipment left in the transport are also lost.

TFTD V2.0 and greater

TFTD V2.0 covers the Dos version with the v2.0 or v2.1 patches installed. The (Windows )Collectors Edition is v2.0 by default. Presumably the Playstation 1 edition is also v2.0 by default.

With the patch, successfully clearing the first part will allow you to take home recoverable equipment if you complete the second map, or abort the second map early with at least 1 conscious aquanaut in the exit area. Basically the transport sub must be able to fly back home.

What equipment recovered on the first map will vary on how you ended it. If you ended it by way of ending the turn with troops in the exit area, only equipment that is in or has been left in the troop transport is recovered.

If you clear the whole map of aliens, then everything on the first map that can be picked up will be returned to base.

Live Aliens

Live aliens will not be carried over between maps in any version of X-COM or TFTD.

The technical reason behind this is due to the fact that the UNITREF.DAT entry is not transferred to the second stage map, only the physical object that represents its body. Once a body item becomes disassociated with the stats that make it what it is, then it reverts to being a corpse item

In TFTD, if you find an alien on the first map that you must capture, you must abandon the mission early and leave with the (stunned) live alien in the transport sub.

In the second part, you have to clear the map completely or leave with the (stunned) alien in the exit area.