Imprisoned Deathlord can be obtained from core set packs or Soul Summoned for 400 Soul Gems.
This card has very high stats for its cost, but an equally large drawback. Enemies can render this card almost useless by simply summoning at least one creature per turn.
Giving this card Guard lets the player put its high attack and health to use by forcing the opponent to attack into it. Alternatively, one can Silence this card, turning it into a powerful attacker with no drawbacks.