Obtained from Decisive Battle of the Valkyries event.
Grants a 10% Skill Boost if Main Card has Slash skill (25% on Straight+).
This makes Olrun comparable (if slightly better) than similar S-rarity cards.
When subbed alongside Gondol, Olrun allows Gondol to utilize a 45% Skill Boost.
This makes for a very effective combo of Subs. (Especially for Slash cards.)