Loyalty

Loyalty is a game mechanic introduced in Total War: Warhammer II for the Skaven, Dark Elves, and Vampire Coast. Loyalty is a measure of the willingness of a Lord to follow the leader of his or her faction. If a lord's loyalty reaches 0 they can rebel, taking their army with them, and if it reaches 10 they can gain a unique item.

The faction leader and their army are not affected by loyalty. For instance if you are playing as Naggarond, then Malekith and his army are not affected. Additionally, Vampire Coast lords earned from the technology tree are not affected by Loyalty.

How it works
Loyalty is measured on a scale of 0 to 10, low to high.

A lord's loyalty is displayed in the bottom left, near their portrait, when they are selected.

Should a Lord’s loyalty reach 0 they will rebel, taking their army with them to form a new separatist faction. This is similar to a rebellion which can happen with low public order.

A selected Lord’s loyalty is shown on the Character Info panel, and on the Details tab of the Character Details panel. The starting loyalty for each Lord available for recruitment can take a range of values, indicated on the Recruit Lord panel. Your starting lord has no loyalty statistic and will never abandon your faction.

Additionally, at very high loyalty levels your lord may offer you certain crafted items through a dilemma.

Increasing loyalty

 * Winning a battle with a lord can increase that lord's loyalty.
 * Raiding with an army.
 * Recruiting units into a lord's army.
 * Equipping items, banners and followers to a lord can increase their loyalty.
 * Har Ganeth has a faction mechanic which can cause lord to gain loyalty at the start of your turn, when Hellebron is still fairly young.
 * The Thirteenth Scheme rite for Skaven gives Lords a chance to gain +2 loyalty each turn while it is active.
 * Vampire Coast Lords have traits that say specifically what will increase their loyalty. For example, a firestarter gains loyalty through sacking or razing settlements.

Reducing loyalty

 * Queek Headtaker (Clan Mors) has a character trait which makes any Grey Seers he recruits begin with lower loyalty.
 * It appears that when an army suffers attrition, this can reduce loyalty.
 * Disbanding large numbers of units in a lord's army can decrease their loyalty to avoid crippling a lord just before he goes rogue.

Dark Elves

 * Naggarond Separatists
 * Cult of Pleasure Separatists
 * The Blessed Dread Separatists
 * Har Ganeth Separatists
 * Hag Graef Separatists

Skaven

 * Clan Mors Separatists
 * Clan Pestilens Separatists
 * Clan Rictus Separatists
 * Clan Skryre Separatists
 * Clan Eshin Lords are permanently loyal and will never rebel.

Vampire Coast

 * Vampire Coast Separatists
 * The Dreadfleet Separatists
 * Pirates of Sartosa Separatists
 * The Drowned Separatists

Dark Elves

 * The Alchemist
 * Satchel of Potions and loyalty -3
 * 750xp for lord, +2500 money, loyalty +2 lord.
 * Assassin!
 * Shroud of Death, Treasury -1000, Loyalty -2
 * Finish Him: Assassin's End: +2000 xp to lord, Melee attack +4 on that lord, Enemy Hero action success chance -10%
 * The Hermit
 * Enslave Her: Loyalty -6, Unique Rod of Briars
 * Spare Her, Slay Another: 1500 xp for lord, loyalty +1,
 * The Beastmaster
 * Boots of Bracchus, loyalty -5
 * Bonus experience +1500, +2 loyalty
 * Insurgents
 * Righteous Wrath
 * Other option
 * The Relic
 * Skull Helmet
 * The Dagger
 * 1 option
 * 2 options offer Aventurine Dagger

Skaven

 * When Rats Fly!
 * Offers choice between +2000 experience for lord, or
 * Rocket Boots
 * Loyal Musk
 * 4 options, see article
 * Dust It Off!
 * 2 options
 * Enriched Warpstone
 * Unknown event
 * Chromatic Armour

Strategy
Disbanding the units in a Lords army will lower their Loyalty and make them revolt with all of their units. This means that you cannot just disband a lord and let them be easily crushed. If you have a problematic low loyalty lord it is generally best to send them to die in combat where they have little chance or against a faction with many armies nearby. Worst case scenario, they die and you are freed from the issue. Best case scenario they succeed and start taking settlements, boosting their loyalty and now you can invest in them again.

Winning battles has a chance to increase loyalty and depending on the type of victory will increase or decrease the chance. Raiding, recruiting units into the lords army and giving them items also can increase a lords loyalty. Lord Skrolk doesnt like warlords and Queek doesnt like grey seers.