Time Units

Time Units

Time units or TUs are one of several vital resources available to X-COM Soldiers.

A single game turn is an unspecified amount of time. There has been many arguments as to what duration of time this could be, but no one can agree on a hard figure. Here's one example of a detailed estimate. Maybe it's a minute, maybe it's 5 seconds. In any case, a game turn is merely the duration in which actions are taken by each side.

The Time Unit is a fraction of this time. If a soldier has a maximum of 64 Time Units, then each TU is worth 1/64th of a turn. A soldier with 80 TUs uses 1/80th of the turn for every TU spent. This means that Time Units are synonymous with speed.

Starting Values

New recruits will always begin with a value between 50 and 60 time units.

Improvement

TU points are awarded (at end of mission) any time you perform at least one primary action. Just one action is enough - additional ones do not cause more TU points to be awarded.

The possible points earned are dependent on your current TUs. At recruit minimum (50 TUs), an average of 2.2 points are earned. This slopes evenly down to where, at cap minus one (79), an average of 1.0 points are earned (range 0-2).

Maximum Caps

A soldier's TUs caps at 80, but it is possible to 'overflow' the cap by one point on the last combat when you go over the cap. On average, you have a 25% chance of getting capped at 81 instead of 80. Once at 80+, all TU improvements cease.

Older versions of X-COM did not have a cap and stats could reach 255 and then wrap back to 0. This could potentially cripple an otherwise good soldier.

Time Unit Expenditure

Time Units are spent in two ways. In fixed amounts and in percentages.

Fixed Costs

Actions such as walking, turning, moving equipment around, reloading weapons, using medicine and a variety of other actions all cost the same amount of TUs no matter the soldier. (For a table of TUs for moving inventory, see below.) Soldiers with high TUs benefit the most from fixed TU actions more than soldiers with low TUs. Scouts benefit from high TUs the most. Dedicated medics and psi troopers can also benefit from high TUs

Percentage Costs

Actions that cost a percentage, such as firing a gun or priming a grenade, will always take a percentage of the soldier's base Time Units to perform. This means that the amount of TUs has no bearing on how many times the action can be performed during any given turn. For example, if a weapon costs 25% to fire, it can only be fired a maximum of 4 times a turn, for every soldier, regardless of his/her amount of TUs. It is recommended that low-TU soldiers are given long range support fire roles.

Note: Costs are based on the maximum amount of your soldier's TUs. Not the current amount. Therefore, if your current amount is under the maximum, or above the maximum (brought on by going berserk), percentage costs will remain the same.

Note: Due to integer rounding, some TU values will allow certain weapons to be fired more than usual. For example, a solder firing a heavy plasma with auto-fire (35% TUs) will get 3 rounds at some TU values but not others.

Encumbrance

Encumbrance is the weighing down, or burdening, of a soldier. Any weight over the soldier's strength stat will cause encumbrance. This lowers their available TUs, essentially slowing them down.

Formula:

Encumbrance = Strength / Carried Weight*


If Encumbrance >= 1 then

   Available TUs = Base TUs

Else

   Available TUs = INT(Encumbrance x Base TUs)

Example:

A low-end Rookie with a base of 50 TUs, 20 strength, and carrying 80 weight units, will
have an encumbrance of 25%, leaving him with a meager 12 TUs per turn. 

*If Carried Weight = 0, then Carried Weight = 1

Fatal Wounds

Each fatal wound to the left or right leg reduces the soldier's TUs by 10%.

Influences

• Time Units heavily influences a unit's Reactions.
• Closely associated with TUs is the Energy stat.
  • A moving unit consumes both TUs and Stamina (Energy) points. How many energy points are consumed depends on the type of terrain the unit is walking on. More difficult terrain consumes more energy and time units. All other actions only consume TUs.
  • Energy recovery is calculated by taking your soldier's initial time units (the TUs they had as a new recruit) and dividing this by three. Drop the fraction. This will be the soldier's energy recovery rate throughout the campaign. For more details, see Energy.

TU Costs for Moving Inventory

                   To...
                  Ground Hand  Leg   Belt Shoulder Backpack
From... Backpack    10    8     16    12     14       -   
        Shoulder     4    3     12    10      8      16   
          Belt       6    4     10     -     12      16   
          Leg        6   4,6    10    10     10      18   
          Hand       2    4    8,10    8     10      14   
         Ground      -    8     10    12     12      20   

MikeTheRed: Apologies - I never saw JFG & Z's table and made my own anew - GMTA! (I missed the leg's "handedness"!) Where was it linked from? Anyway, we really only need one. Is here a good place? Or maybe the Main Page's Supplementary Reference? This seems as good a place as any, shrug. How about if we dump the other page but move the acknowledgement here? (You two did it first, and better!):

--JellyfishGreen 14:14, 23 May 2005 (BST) with data from Zombie's studies

For the same place (e.g. going From Hand, To Hand) means e.g. switching from left hand to right hand. If there are two numbers, there is an extra cost for switching sides (e.g., left hand to right leg). There is no cost for moving things around within the same area (e.g. a different belt square).

• TU costs are fixed. They aren't affected by soldier stats (energy, strength, even MC'd alien), nor by weight or size of items.
• The shoulder is best for small items. It takes the least time to get to hand. It's also best for dropping to ground (not counting the hand).
• The leg is best for picking stuff up off the ground (10 TUs, not counting hand's 8).
• When picking up stuff that you may want in your hand later, overall the leg on the same side as the hand (10 now, 4 later) is a little quicker than (either) shoulder (12 now, 3 later). If you have plenty of TUs now though, you might use the shoulder since it will need less TUs later (for either hand).
• Of course, 2-square items (MedKit, pistol, blaster bomb) should go on your belt. It's 4 TUs to your hand vs. 8 from backpack.
• In general, it takes longer to go up than down, and longer to go "farther". Backpack is the worst.
• Loading ammo takes 15 TUs, no matter where the ammo comes from (even backpack or ground). Since it doesn't matter where you put ammo, consider your backpack if pressed for space.
• It always takes 8 TUs to unload a weapon (including pistols), no matter where the weapon is coming from (already in hand, from ground, even from backpack).

I've seen an old FAQ that talked about the "alien inventory bug", where if you pick up something from a leg slot with more than one item in it, but don't have enough TUs to put the item down, you're screwed - you have to quit the game. But actually, you can simply put it in the other (empty) left leg square. This doesn't cost any TUs, so it's doable. Just don't screw up again, soldier!

See Also

Inventory TU Table

Reactions

Energy

Strength

Raw recruit statistical likelihood