Adjutants return in Three Hopes, and from the demo the mechanic seems pretty busted. Units on the battlefield can be assigned as adjutants either via orders or by using the L menu while nearby. While controlling a unit that has an adjutant assigned, the lead unit will gain a variety of benefits that are described below. The lead unit can be easily swapped by pressing L + A.

The adjutant unit seems to gain a substantial amount of experience whenever the lead unit defeats an enemy commander, which makes this a great way to level up weaker units without spending money at the Training Instructor. Adjutant units do not seem to gain much (if any) extra class experience, but it's easy to simply weaken an enemy commander with a stronger unit, then swap the lead to a weaker adjutant unit for the final blow.

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If the two units have a C/B/A support level, it grants the lead unit access to the adjutant unit's level 1/2/3 support and tactical abilities. For example, if Ferdinand von Aegir is Hubert's adjutant and they have a C support, Hubert will restore a little bit of Awakening Gauge upon defeating an enemy commander thanks to Ferdinand von Aegir's support ability Name Drop.

Having an adjutant assigned will give stat bonuses to the lead unit based on the adjutant unit's class. Support level will also increase these bonuses by a small amount. Base adjutant stat bonuses for every class are listed below.

While an adjutant is assigned, dealing damage and taking damage will fill the Adjutant Guard Gauge. Taking damage causes it to fill much faster than dealing damage. The higher the support level between the units, the faster this gauge fills.

Once the Adjutant Guard Gauge is filled, the adjutant will step in to block the next instance of damage. This will reset the gauge back to empty. The Adjutant Guard Gauge is shared between the units, regardless of who is currently leading.

Dealing and taking damage will also fill the Adjutant Follow-Up Gauge. Unlike the Guard Gauge, this one fills at about an equal rate for both dealing and taking damage. The higher the support level between the units, the faster this gauge fills.

Once the Adjutant Follow-Up Gauge is filled, the next knockback attack will trigger an Adjutant Follow-Up attack, where the adjutant appears and does a good amount of damage to the attacked enemy. This will reset the gauge back to empty. The Adjutant Follow-Up Gauge is also shared between the units, regardless of who is currently leading.

When a unit with an adjutant uses their Warrior Special, the adjutant will first use their Warrior Special as well regardless of their Warrior Gauge. A partner special does not deplete the adjutant's Warrior Gauge at all, which essentially means that you get an entire extra Warrior Special for free. Partner Specials also works on the free Warrior Special that happens when exiting the Awakened state.