Pair Up

Pair Up is a feature introduced in Version 3.4.0 that allows two units to occupy the same tile on a map, boosting their stats and allowing them to switch places at any time. It can be found under the Interact with Allies menu.

Details
This feature is only available to use in the Main Story, Paralogues, Training Tower, Allegiance Battles, Røkkr Sieges, and Mjölnir's Strike. In all of these modes except for Allegiance Battles and Mjölnir's Strike, Pair Up is only available to Legendary Heroes that possess the Pair Up ability. In Allegiance Battles, however, the Hero in the rightmost team slot may be paired up with a friend's unit, even if neither is Legendary nor possesses the Pair Up ability.

From the Pair Up menu, applicable Legendary Heroes can be assigned a partner unit. When that Legendary Hero enters a map and their partner is not otherwise on the team, the two will enter the map as a pair.

Each pair has one unit in front: the leader, and one unit in back: the cohort. These roles can be switched at any time, even after performing an action during a turn. During combat, the cohort will appear behind the leader, and the leader will receive a stat boost according to the stats of the cohort. Combat then proceeds using the resulting stats and skills of the leader, ignoring the skills, Legendary Effects, and Ally Support Effects of the cohort. Only the leader at a given time can obtain EXP and SP at the end of combat, as well as HM when the map is cleared.

If either unit of a pair possesses a skill like or, other units cannot use skills like Sing or Dance on that pair at all.

If the leader of a pair is defeated, then their cohort will be defeated as well, except in Allegiance Battles and Mjölnir's Strike.

Stat Boosts
The stat boost granted to the leader during Pair Up is calculated depending on the cohort's stats prior to the beginning of a map, with a maximum boost of +4 to each stat, rounded down. Each stat's boost is calculated separately. Stat alterations that occur after starting a map, such as Blessing effects, set: bonuses, set: penalties, combat boosts, and combat reductions are not considered in this calculation.

As such, the pre-map cohort stats required for the leader to receive at least +1 boost to each stat are 35 Atk and 20 Spd/Def/Res. The cohort stats required for the maximum +4 boost are 65 Atk and 50 Spd/Def/Res.