Leblanc legend wins a combat with a 3 might unit that has assault 2. They trigger the legend to create a reflection token. It will be a 3 might unit as it copies base might, but does it have assault temporarily while the chain finishes resolving?

No, the Reflection token will not have Assault (or the +2 Might bonus) while the chain is resolving.

According to the rules regarding copy effects and the provided FAQs, here is the breakdown:

1. Copyable Traits vs. Modifiers

When the Reflection token becomes a copy, it only adopts the "copyable traits" of the target unit. As established in RiftJudge FAQ #10455, #10887, and #10200, these traits are limited to the unit's printed characteristics (base Might and Rules Text).

• Assault is a keyword/ability, which is a copyable trait. Therefore, the Reflection token will gain the Assault keyword when it becomes a copy of the unit.
• However, the +2 Might bonus granted by the unit's Assault keyword is a temporary modifier active during combat. It is not a copyable trait. The Reflection token does not inherit active, temporary buffs or the current state of the target's Might.

2. Assault Timing

The Assault keyword is defined by Rule 807.1.c as: "While I am an attacker, I have +X [M]." For a unit to benefit from Assault and gain the Might bonus, it must currently possess the Attacker designation.

• When the Reflection token enters the battlefield, the combat showdown has concluded (the win has already triggered the Legend ability).
• Even if the Reflection token gains the Assault keyword as part of its copy effect, it does not currently hold the Attacker designation (designations are removed during the Combat Cleanup phase, which precedes the conquer trigger).

Summary

While the Reflection token will successfully gain the Assault keyword because it is part of the copied unit's printed Rules Text, it will not receive the +2 Might bonus because:

1. The Might bonus is a temporary modifier, not a copyable trait.
2. The unit is no longer an "attacker," so the condition for the Assault ability is not met.

The Reflection token will enter the battlefield as a copy of the unit, but with the base Might printed on the original card (e.g., 3 Might).