Xun Yu, Wei AdvisorHow it works & interactions with other cards

Tactical Timing and Restrictions

Xun Yu, Wei Advisor features a restricted activated ability that grants a target creature you control +2/+0 until the end of the turn. The most important constraint is the timing: you may only activate this during your own turn and only before attackers are declared. This means you must act during your Beginning Phase, your Main Phase, or the Beginning of Combat step. Once you move to the Declare Attackers step and name your attacking creatures, it is too late to use this ability for that combat.

Resolution Step-by-Step

When you activate the ability, you first confirm it is your turn and that you have not yet declared attackers. You tap Xun Yu, Wei Advisor as the cost and choose a target creature you control. Upon resolution, the target gains the +2/+0 bonus. If the target creature becomes illegal before resolution (for example, if it leaves the battlefield), the ability fails to resolve and no bonus is applied.

Multiple Combat Phases

A common point of confusion arises when players have multiple combat phases in a single turn. According to official rulings, if a turn has multiple combat phases, Xun Yu's ability can only be activated before the beginning of the declare attackers step of the very first combat phase. You cannot wait until the second combat phase to activate his ability.

Strategic Implementation

Because the bonus lasts until the end of the turn, you don't necessarily have to use it on a creature that is about to attack. You can use it to buff a creature to survive certain 'power-matters' checks or simply to prepare a blocker if you have a way to untap the creature later. However, its primary use is to push through extra damage during your combat step.

Interaction examples

Enhancing the Automaton

Solemn Simulacrum

During your Pre-combat Main Phase, you tap Xun Yu, Wei Advisor targeting your Solemn Simulacrum. The Simulacrum becomes a 4/2 creature. You then move to combat and declare it as an attacker. The +2/+0 bonus persists even after combat, so if the Simulacrum dies during the post-combat Main Phase, it was still a 4/2 at the moment it took lethal damage.

The Advisor's Limitation

Roaming Throne

If you control Roaming Throne and chose 'Human' as it entered, note that Roaming Throne only doubles triggered abilities. Because Xun Yu, Wei Advisor has an activated ability (indicated by the 'Cost: Effect' format), the Throne does not allow the ability to trigger a second time. You still only get one instance of +2/+0 for tapping the Advisor.