The Wyvern Knight (ワイバーンナイト Waibān naito) is a Wyvern-mounted combat physical class that appears exclusively in Fire Emblem: The Sacred Stones. One of the promoted forms of the Wyvern Rider and Pegasus Knight classes, Wyvern Knights are solely armed with Lances as their weapon of choice. Like their preceding class, Wyvern Knights are weak against Bows and Anti-Dragon weapons like the Dragonpike.
Wyvern Knights are renowned for the Pierce skill that they possess, allowing them to bypass the enemy's Defense when activated, in turn resulting in each attack inflicting a sizeable amount of damage. Pierce can be stacked with a Critical hit, a fact that further amplifies the strength of each attack by a devastating amount.
A well-known glitch is associated with the Pierce skill, however; this glitch causes the game to freeze, and occurs as a result of its user activating Pierce on the first hit but failing to kill the enemy and thereafter attacking a second time without the enemy retaliating. This glitch does not occur when battle animations are turned off or in the original Japanese release.
The Triangle Attack, originally a move that can only be performed by a set of three Pegasus-based characters, can still be performed with Wyvern Knights, but only if the player has one Wyvern Knight and two Pegasus or Falcon Knights, alongside a requisite for the Wyvern Knight character to initiate the attack.
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C
Wyvern Rider
Elysian Whip or a 
Master Seal on a Level 10+ Wyvern Rider.
Wyvern Knight
Pegasus Knight
