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>However, it is advised not to play with Greavard too often, as it is known to slowly and unwittingly drain the life-force of those near it.
Actually, none of Greavard's in game abilities do this, and it doesn't learn any Poison type moves either.
According to my damage calculations, 252 Atk Life Orb Corviknight will OHKO Greavard without taking any damage from Greavard, making Greavard's lore non-canon.
This post was brought to you by the Corviknight Council of Smogon, a fact checking task force dedicated to debunking the inaccurate and lazy "lore" that Game Freak spreads. This poorly thought out "lore" leads to misconceptions that spread throughout the casual playerbase, such as the belief that Tinkaton can defeat Corviknight in battle, even though in-game stats and calculations based on the current Smogon National Dex OU meta prove otherwise.