The Immortal Bushi (PTDN-EN029) - Phantom Darkness Unlimited

This card cannot be Tributed, except for the Tribute Summon of a Warrior-Type monster. During your Standby Phase, if this card is in your Graveyard and you control no monsters, you can Special Summon it. You cannot activate this effect if there are any monsters in your Graveyard that are not Warrior-Type.