Gisela, Blade of Goldnight is a mythic Legendary Creature — Angel card from Commander 2015 (C15), collector number 219. Current market price: $5.43, TCGplayer market prices via Scryfall.
Flying, first strike If a source would deal damage to an opponent or a permanent an opponent controls, that source deals double that damage to that player or permanent instead. If a source would deal damage to you or a permanent you control, prevent half that damage, rounded up.