Reanimation is not a proper term used by the game, this page merely groups together vaguely similar traits and units that can be then described as "reanimation".

A number of spells and abilities can reanimate the undead. This page lists these spells and abilities, as well as the special national undead that can be summoned by certain nations.

A basic rule of thumb is that most reanimated undead are mindless troops; usually with 15 Cold Resistance, 25 Poison Resistance, and with at least the traits Need not Eat, Never Heals, and Inanimate.

Generally, most reanimated undead can be grouped into 2 categories: Longdead and Soulless.

• Longdead are also known as skeletons; they are usually resurrected warriors and so are often armed with weapons and armor. They have Attack and Defense stats similar to a trained human, but usually have barely more than half the hitpoints of their living equivalent. Notably, they usually have Spirit Sight and Pierce Resistance.
• Soulless are also known as zombies; they are raised from the corpses of civilians as much as warriors, with lower than normal Attack and Defense stats relative to both cases. They also usually have higher strength and more hitpoints than their living equivalent. Notably, they are usually Undisciplined and do NOT have Darkvision or Spirit Sight.

• Unlife Damage: Units killed by this effect will spawn a new Soulless.
  • Shade Beast's Reanimating Bite deals this type of damage
  • The Construction 6 Two handed Weapon Ivory Bow and the Construction 8 Artifact One handed Weapon Twin Spear both deal this type of damage
  • The spells Bolt of Unlife, Blast of Unlife, and Vortex of Unlife all deal this type of damage
  • How does this choose what type of Soulless to spawn?

• Reanimation Buff: Units killed while under the effect of this buff will rise again for their own side and continue fighting as Soulless with any magic paths and/or commander status intact.
  • The spell Life after Death applies this effect to all non-mindless friendly units.
  • The effect can be applied to but will fail to activate for: Undead, Immortals, Demons, Inanimates, creatures that are inherently Ethereal, Pretenders, and most kinds of Animals. There are also exceptions on a unit by unit case, as seen on here: Loggy's Misc Notes
  • How does this choose what type of Soulless to spawn?

• Reanimator : Units killed by this unit have a chance equal to the value of their killer's Reanimator trait to spawn an ally of the killer. This is by default a Soulless, but can be something else if the unit also has the "raiseshape" trait.
  • In the base game, there are 2 units with this trait that use it to create Soulless: Mound Fiend and Gorilon - Heliophagus
  • How does this choose what type of Soulless to spawn?

• Reanimator Priest : A commander with this ability can spend a turn to reanimate a variable amount of undead, depending on their Holy level and the Nation that owns them. For more information, see the section on the Priestly Reanimate order further down.
  • EA Lanka and MA Sceleria have recruitable commanders with this ability
  • MA Ermor and LA Lemuria provide all priests they own with this ability for as long as they are owned
  • MA Asphodel and LA C'tis provide all undead priests they own with this ability for as long as they are owned
    • This does not prevent living commanders who have the ability from using it

• Reanimator2: A commander with this ability will passively raise this many corpses per month as Soulless. This ability has no icon, is normally called Reanimator just like the Raise on Kill effect but is called Reanimator2 here just to differentiate, and is currently only used on God Vessel.
  • How does this choose what type of Soulless to spawn?

• Reanimation Bonus : A commander with this ability produces as additional amount of troops when reanimating. This ability has two different values, a Priestly reanimation bonus and a Magical reanimation bonus.
  • MA Nazca's recruitable commanders of Mallqui Priestess, Mallqui Priest, and Royal Mallqui have this ability with an equal value for their priestly/magical bonus
  • MA Nazca's Manco-Ocllo - First Couple hero, and EA/MA/LA Mictlan's Mictlipoctli - King of Legends hero both have this ability with an equal value for their priestly/magical bonus
  • 6 pretenders and Bune - Ice Devil, who all lack any Holy paths, have this ability with a 0 for priestly bonus
  • The Construction 4 Miscellaneous Item Amulet of the Dead and the Construction 8 Artifact Crown The Crown of Despair both provide this ability
  • What spells and orders does this affect again? Like I remember it working for Longdead and Longdead Horsemen but not Lictors or Ghouls.

• A priest with this order will automatically continue to repeat it on subsequent turns, like a mage with the "monthly forging/casting" box ticked on.
• There are no working sanity checks when using the Reanimate order. Priests will try to carry it out and repeat order as normal, even when it has no effect. Here are some notable situations.
  • While underwater, and summoning undead that cannot breathe underwater.
  • With no available corpses, and summoning undead that require corpses to create.
  • With no population, and summoning undead that require population.
• Test if the + means that the units are affected by Reanimation Bonus, which seems to be the most likely thing given how Tomb Chariots have the + and Tomb Wyrms do not, but I haven't tested this.
• Asphodel and Lemuria's commanders who have the Reanimator Priest tag (be it naturally or as provided by their dominion) do not have the traditional Reanimate order, instead their order to summon undead is called by a different name.
  • Therodos has Call Spectres
    • This has no alternate options, and therefore no choice or menu to select
  • Asphodel has Awaken Manikins
    • This has no alternate options, and therefore no choice or menu to select
  • Lemuria has Call Spirits

Default Reanimation Orders
Priest Level	Ghouls	Soulless	Longdead Warriors
1	6+	8+	3+
2	7+	16+	5+
3	8+	24+	7+
4	9+	32+	9+
5	10+	40+	11+
6	11+	48+	13+
7	12+	56+	15+

EA Theredos Reanimation Orders
Priest Level	Call Spectres
1	???
2	???
3	???
4	???
5	???
6	???
7	???

MA Sceleria Reanimation Orders
Priest Level	Ghouls	Soulless	Longdead Warriors	Longdead Horsemen
1	6+	8+	3+	N/A
2	7+	16+	5+	1+
3	8+	24+	7+	2+
4	9+	32+	9+	3+
5	10+	40+	11+	4+
6	11+	48+	13+	5+
7	12+	56+	15+	6+

MA Ermor Reanimation Orders
Priest Level	Ghouls	Soulless	Longdead Warriors	Longdead Horsemen	Lictors
1	6+	8+	3+	N/A	N/A
2	7+	16+	5+	1+	N/A
3	8+	24+	7+	2+	1
4	9+	32+	9+	3+	2
5	10+	40+	11+	4+	3
6	11+	48+	13+	5+	4
7	12+	56+	15+	6+	5

MA Nazca Reanimation Orders
Priest Level	Ghouls	Soulless	Longdead Warriors	Supayas
1	6+	8+	3+	N/A
2	7+	16+	5+	N/A
3	8+	24+	7+	2
4	9+	32+	9+	3
5	10+	40+	11+	4
6	11+	48+	13+	5
7	12+	56+	15+	6

MA Asphodel Reanimation Orders
Priest Level	Awaken Manikins
1	???
2	???
3	???
4	???
5	???
6	???
7	???

LA C'tis Reanimation Orders
Priest Level	Ghouls	Soulless	Longdead Warriors	Tomb Wyrms	Tomb Chariots
1	6+	8+	3+	N/A	N/A
2	7+	16+	5+	1	N/A
3	8+	24+	7+	2	2+
4	9+	32+	9+	3	3+
5	10+	40+	11+	4	4+
6	11+	48+	13+	5	5+
7	12+	56+	15+	6	6+

LA Lemuria Reanimation Orders
Priest Level	Dispossessed Spirits	Shadows	Shade Beasts	Apparitions
1	10	2	N/A	N/A
2	12	3	1	1
3	14	4	2	2
4	16	5	3	3
5	18	6	4	4
6	20	7	5	5
7	22	8	6	6

The tables shown here are based off of testing. However, what was tested was only what the nations listed as special when it comes to undead reanimation in the modding manual. Said modding manual is the very same that just flat out states the wrong priest level for what is needed to summon Longdead Horsemen and Lictors.
Seperate from the nation tables, add the ingame description of each of the options and hopefully figure out a way to see what they actually do.

If you don't have nationals, just use the fallback output.
The chances to pull from the "national pool" varies depending on the creation method:

• Effect 37 rituals, (remote summons, like Army of the Dead)
  • 50% chance of national longdead for Commander
  • 10% chance of national longdead for Troops

• Effect 1 rituals, (summons, like Reanimation)
  • 100% chance of national longdead

• Priest Reanimation order, chance depends on your nation:
  • MA Ermor, Sceleria:
    • 10% chance of national longdead
  • Niefelheim, Jotunheim, Utgard:
    • 25% chance of national longdead
  • Hinnom, Ashdod:
    • 50% chance of national longdead
  • Any other nation:
    • 75% chance of national longdead

• Otherwise, there is a 10% chance to get nationals.

• Equal chance to: pick one of these 6; Longdead-191, Longdead-192, Longdead-193, Longdead-194, Longdead-195, Longdead-196

• 50% chance to use fallback,
• Otherwise:
  • 100% chance for: Longdead Giant-316

• 50% to use fallback,
• Otherwise:
  • 50% chance for: Longdead Giant-2484
  • Else: Longdead Giant-316

• 50% chance to: pick Longdead Velite-186 or Longdead Legionnaire-187,
• Else: pick Longdead Triarius-1657 or Longdead Principe-1658

• Equal chances to: pick one of these 3 Longdead-2120, Longdead-2121, Longdead Hoplite-2122

• 85% chance to: pick Longdead-3360 or Longdead-3361,
• Otherwise: use Longdead-2123

• Equal chances to: pick Longdead-2123 or Longdead-2124

• 75% chance for: Longdead-2124,
• Otherwise: use fallback

• 25% chance to: use Longdead-3361,
• Otherwise: use fallback.

• Equal chances to pick one of these 5; Longdead of C'tis-615, Longdead of C'tis-616, Longdead of C'tis-617, Longdead Warrior-618, Longdead Warrior-619

• Equal chances to pick one of these 4: Caelian Longdead-2703, Caelian Longdead-2704, Caelian Longdead-2705, Caelian Longdead-2706

• Equal chances to: pick Nazcan Longdead-2701 or Nazcan Longdead-2702

• 50% chance to: pick one of these 3; Longdead Rephaite-2041, Longdead Rephaite-2042, Longdead Rephaite-2043,
• Otherwise: use fallback

• 2/7 chance to: pick one of these 3; Longdead Bandar-1720, Longdead Bandar Warrior-1721, Longdead Bandar Warrior-1722,
• 1/7 chance to: pick one of these 3; Longdead Vanara-1727, Longdead Vanara Warrior-1728, Longdead Vanara Warrior-1729,
• Otherwise: use Longdead Markata-1732

• 15% chance to: use Longdead-2124,
• Otherwise: pretend you are EA Berytos

• 50% chance to: pick Longdead-2120 or Longdead-2121,
• Otherwise: use Longdead-2451

Each soulless request looks at a few things:

• The nation creating soulless
• The province ID the soulless are being made in
• A chance for national soulless
• A chance for arming soulless
• The number of corpses to subtract

Sources and values for national and arming rates for the above:

• Montag -3:
  • 10% national, 100% ArmingChance

• Montag -15:
  • 25% national, 50% ArmingChance

• "newunit" called with unit ID -1, unknown if this is used:
  • 10% national, 100% ArmingChance

• Battlesummon, damage -3:
  • 10% national, 100% ArmingChance

• Reanimator priests:
  • 90% ArmingChance, but national rate varies:
    • If Jotunheim, 50% national
    • If Utgard, 25% national
    • Any other nation:
      • Reanimator priest holy level is considered as 1 higher if ((closed d5 - 1) < number of friendly candles) in province,
      • National soulless rate = (reanimator priest's holy level * 8)%

• Rituals, effect number 1 [summons, though there are no base game rituals that summon Soulless this way]:
  • 100% national, 90% ArmingChance

• Rituals, effect number 37 [remote summons, like Carrion Reanimation]:
  • Units:
    • 10% national, 10% ArmingChance
  • Commander:
    • 50% national, 90% ArmingChance

• If there is a province ID associated with this creation:
  • Roll soulless ArmingChance, if successful proceed as making Lightly Armed soulless
  • Otherwise, if (Civilian corpses < Military corpses):
    • Proceed as making Lightly Armed soulless
• Armed Soulless upgrade chances:
  • In EA,
    • 25% chance to: upgrade Lightly Armed to Medium Armed soulless
  • In MA,
    • 50% chance to: upgrade Lightly Armed to Medium Armed, and if that succeeds:
      • 25% chance: to upgrade to Heavy armed soulless (total of a 1/8 chance)
  • In LA,
    • 75% chance to upgrade Lightly Armed to Medium Armed, and if that succeeds:
      • 50% chance: to upgrade to Heavy Armed soulless (total of a 3/8 chance)
• If there wasn't a province ID, you always get Unarmed soulless

• If this attempt is subtracting corpses, do that now.
  • Unarmed soulless subtract Civilian corpses
  • Any kind of Armed soulless subtract Military corpses

• Spawn the following unit:
  • Unarmed:
    • Soulless-197
  • Lightly Armed:
    • Soulless Warrior-914
  • Medium Armed:
    • Soulless Warrior-915
  • Heavily Armed:
    • Soulless Warrior-2119
• If the chance for national soulless was a success, then potentially modify the result as shown below.

• Unarmed:
  • 50% chance to become: Soulless Giant-315
• Light, Medium:
  • 50% chance to become: Soulless Warrior-916
• Heavy:
  • 50% chance to become: Soulless Warrior-917

• Unarmed:
  • Becomes: Soulless-317
• Light:
  • Becomes: Soulless Warrior-2242
• Medium, Heavy:
  • Becomes: Soulless Warrior-2243

• Unarmed:
  • 75% chance to become: Soulless Enkidu-2981
• Light:
  • 75% chance to become: Soulless Warrior-2982
• Medium, Heavy:
  • Becomes: Soulless Warrior-2983

• Unarmed:
  • Becomes: Soulless Nazcan2707
• Light, Medium, Heavy:
  • Becomes: any one of these 4; Soulless Nazcan Warrior-2708, Soulless Nazcan Warrior-2709, Soulless Nazcan Warrior-2710, Soulless Nazcan Warrior-2711

• 75% chance to:
  • Unarmed:
    • Becomes: Soulless of Atlantis-318
  • Light:
    • Becomes: Soulless Warrior-919
  • Medium, Heavy:
    • Becomes: Soulless Warrior-920
• Otherwise:
  • Unarmed:
    • Becomes: Soulless Shambler-2364
  • Light:
    • Becomes: Soulless War Shambler-2365
  • Medium, Heavy:
    • Becomes: either Soulless War Shambler-2366 or Soulless War Shambler-2367

• 75% chance to:
  • Unarmed:
    • Becomes: Soulless of Atlantis-318
  • Light:
    • Becomes: Soulless Warrior-919
  • Medium, Heavy:
    • Becomes: Soulless Warrior-920
• Otherwise:
  • Unarmed:
    • Becomes: Soulless Shambler-2364
  • Light:
    • Becomes: Soulless War Shambler-2365
  • Medium, Heavy:
    • Becomes: Soulless War Shambler-2366

• Unarmed:
  • Becomes: Soulless of C'tis-319
• Light:
  • Becomes: Soulless Warrior-921
• Medium, Heavy:
  • Becomes: Soulless Warrior-922

• Roll a closed d7, then,
• If Unarmed, and:
  • 1-2:
    • Becomes: Soulless Bandar-1716
  • 3-5:
    • Becomes: Soulless Vanara-1724
  • 6-7:
    • Becomes: Soulless Markata-1731
• If Lightly Armed, and:
  • 1-2:
    • Becomes: Soulless Bandar Warrior-1717
  • 3-4:
    • Becomes: Soulless Markata-1731
  • 5-7:
    • Becomes: Soulless Vanara Warrior-1725
• If Medium Armed, and:
  • 1-2:
    • Becomes: Soulless Bandar Warrior-1718
  • 3-4:
    • Becomes: Soulless Markata-1731
  • 5-7:
    • Becomes: Soulless Vanara Warrior-1725
• If Heavily Armed, and:
  • 1-2:
    • Becomes: Soulless Bandar Warrior-2274
  • 3-4:
    • Becomes: Soulless Markata-1731
  • 5-7:
    • Becomes: Soulless Vanara Warrior-1725

• Loggy's Longdead and Soulless reverse engineering notes