Eternal Card Game

Exalted is a keyword from a previous expansion (Flame of Xulta). After dying, units with Exalted become a weapon with their stats and battle skills that you can apply to a friendly unit of your choice.

Kodosh's Armor is a Legendary relic from the Echoes of Eternity expansion:
To earn this achievement, you need to get Kadosh's armor into play, then have an Exalted unit die while you have at least five single-faction units in play so that they all receive the Exalted weapon. After doing so and completing the match, the achievement will unlock.