Wary Fighter

Wary Fighter is a skill in the Fire Emblem series that was introduced in Fire Emblem Fates. It is an armor-exclusive skill that prevents either side from performing a second attack. It is a Passive B skill in Fire Emblem Heroes.

Effect
A character with Wary Fighter cannot double attack or be doubled attacked by an enemy unit regardless of either unit's speed. The skill does not protect against against the effect of Brave weapons which will still do 2 attacks in a row regardless.

Fire Emblem Heroes
Like in the main series, Wary Fighter prevents follow-up attacks from either side. However, the skill has an HP activation rate. Additionally, the effect can be circumvented if the unit has more effects that grant follow-up attacks like Hector wielding Armads and having Quick Riposte.
 * Level 1 - If unit's HP ≥ 90%, prevents follow up attacks in combat from unit and foes. Costs 50 SP
 * Level 2 - If unit's HP ≥ 70%, prevents follow up attacks in combat from unit and foes. Costs 100 SP
 * Level 3 - If unit's HP ≥ 50%, prevents follow up attacks in combat from unit and foes. Costs 200 SP

Availability
In Fire Emblem Fates, the skill is learned by Generals at level 5 or higher.

Fire Emblem Heroes
Wary Fighter can only be learned by Armored units. The skill is learned natively with the following units.
 * Effie (4 stars)
 * Zephiel (4 stars)
 * Surtr
 * Jakob (Trick or Defeat!)
 * Chrom (Winter's Envoy)
 * Hector (Love Abounds)
 * Dorcas (The Land's Bounty)
 * Greil (Greil's Devoted)

Trivia

 * Wary Fighter inspired a line of Armor exclusive skills in Fire Emblem Heroes, mostly to compensate for Armor units' poor speed. These skills include Bold Fighter, Vengeful Fighter and Special Fighter